Article 62

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1. Should a state consider that it has an interest 1. Lorsqu’un État estime que, dans un
of a legal nature which may be affected by the différend, un intérêt d’ordre juridique est
decision in the case, it may submit a request to pour lui en cause, il peut adresser à la Cour
the Court to be permitted to intervene. une requête, à fin d’intervention.
2. It shall be for the Court to decide upon this 2. La Cour décide.
request.

mn
A. Introduction 1–​3
B. Historical Development 4–​10
I. Antecedents 4–​5
II. The Travaux Préparatoires of the Statute of the Court 6–​8
III. Persistent Difference of Wording between the French and English
Versions of the Statute 9–​10
C. Practice of Intervention under Article 62 11–​15
D. Characteristics of Intervention under Article 62 16–​33
I. Intervention as Incidental Proceedings 16–​24
II. Intervention as Statutory Jurisdiction 25–​27
III. The Margin of Appreciation of the Court 28–​29
IV. Intervention and the Indispensable Third Party 30–​33
E. Requirements for Intervention under Article 62 34–​114
I. Evolution of the Rules of the Court 35–​37
II. Procedural Conditions 38–​43
III. Substantive Conditions 44–​102
1. Interest of a Legal Nature Which May Be Affected 45–​74
a) The Interest of a Legal Nature 46–​57
aa) The Legal Nature 47
bb) The Distinction between the Legal Interest and the
Legal Right 48–​51
cc) A Concrete and Individualized Interest 52–​57
b) The Risk for the Interest to be Affected by the Decision 58–​71
aa) Interpretation of the Term ‘decision’ 58–​59
bb) A Circumstantial Assessment 60–​71
c) Relationship between Articles 62 and 59 of the Statute 72–​74
IV. The Object of Intervention 75–​90
1. The Improper Object: Intervention Must Not Introduce a
New Dispute 77–​83
2. The Proper Object: Protection of Legal Interests and Information
of the Court 84–​85
3. Degree of Specificity of the Application 87–​90
4. The Jurisdictional Link 91–​102
V. Evidentiary Requirements 103–​114
1. Evidence and Standard of Proof 103–​106
2. Access to Written Pleadings 107–​114
F. Procedures for Consideration of a Request to Intervene 115–​120

miron/chinkin
The Statute of the International Court of Justice: A Commentary. Third Edition. Edited by Andreas Zimmermann and Christian J. Tams,
Oxford University Press. © The several contributors 2019. DOI: 10.1093/law/9780198814894.003.0078
 Article 62 1687
G. The Status of the Intervener 121–​135
I. The Distinction between Intervention as a Party and
Intervention as a Non-​Party 121–​128
II. The Procedural Rights of the Intervener 129–​135
H. Intervention in other Fora 136–​142

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I. Evaluation 143–​147

Select Bibliography
Bonafé, B., ‘Interests of a Legal Nature Justifying Intervention before the ICJ’, Leiden JIL 25
(2012), pp. 739–​57
Chinkin, C., ‘Third Party Intervention before the International Court of Justice’, AJIL 80 (1986),
pp. 495–​531
—​—​—​, Third Parties in International Law (1993), pp. 147–​85
Davi, A., L’intervento davanti alla Corte Internazionale di Giustizia (1984)
Decaux, E., ‘L’intervention’, in SFDI, Juridiction internationale, pp. 219–​55 (1987)
Doussis, E. ‘Intérêt juridique et intervention devant la Cour internationale de Justice’, RGDIP 105
(2001), pp. 55–​91
Elias, T., The International Court of Justice and Some Contemporary Problems (1983)
Farag, W., L’intervention devant la Cour Permanente de Justice Internationale (Articles 62 et 63 du
Statut de la Cour) (1927)
Fritzemeyer, W., Intervention in the International Court of Justice (1983)
Greig, D.W., ‘Third Party Rights and Intervention before the International Court’, Va. JIL 32
(1992), pp. 285–​376
Iwasawa, Y., ‘WTO Dispute Settlement as Judicial Supervision’, JIEL (2002), pp. 287–​305
Jiménez de Aréchaga, E., ‘Intervention under Article 62 of the Statute of the International Court of
Justice’, in Völkerrecht als Rechtsordnung, Internationale Gerichtsbarkeit, Menschenrechte: Festschrift
für Hermann Mosler (Bernhardt, R., et al., eds., 1983), pp. 453–​65
Licari, T., ‘Intervention under Article 62 of the Statute of the ICJ’, Brooklyn JIL 8 (1982), pp. 267–​87
Miller, J., ‘Intervention in Proceedings before the International Court of Justice’, in Gross, The
Future of the ICJ, pp. 550–​71
Miron, A., ‘Intervention’, in Nicaragua before the International Court of Justice: Impacts on
International Law (Samson, B./​Sobenes, E., eds., 2017), pp. 371–​96
Murphy, S., ‘Amplifying the World Court’s Jurisdiction through Counter-​Claims and Third Party
Intervention’, Geo. Wash. Univ. Int’l L. Rev. 33 (2000–​2001), pp. 5–​30
Oda, S., ‘Intervention in the International Court of Justice: Articles 62 and 63 of the Statute’,
in Völkerrecht als Rechtsordnung, Internationale Gerichtsbarkeit, Menschenrechte: Festschrift für
Hermann Mosler (Bernhardt, R., et al., eds., 1983), pp. 629–​48
—​—​—​, ‘The International Court of Justice Viewed from the Bench (1976–​1993)’, Rec. des Cours
244 (1993), pp. 9–​190
Palchetti, P., ‘Opening the International Court of Justice to Third States: Intervention and Beyond’,
Max Planck UNYB 6 (2002), pp. 139–​81
Registry of the ICJ, ‘The Form of the Decisions of the Court for the Purposes of Incidental
Proceedings and Proceedings on Interpretation or Revision’, ICJ Yearbook (2014–​2015),
pp. 84–​104
Rosenne, S., Intervention in the International Court of Justice (1993)
Ruda, J., ‘Intervention before the International Court of Justice’, in Fifty Years of the International
Court of Justice: Essays in Honour of R. Jennings (Lowe, V./​Fitzmaurice, M., eds., 1996),
pp. 487–​502
Ruiz-​Fabri, H./​Sorel, J.-​M. (eds.), Le tiers à l’instance devant les juridictions internationales
(2005)

miron/chinkin
 1688 Statute of the ICJ
Torres Bernárdez, S., ‘L’intervention dans la procédure de la Cour internationale de Justice’, Rec.
des Cours 256 (1995-​VI), pp. 193–​457
Zimmermann, A., ‘International Courts and Tribunals, Intervention in Proceedings’, Max
Planck EPIL

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A. Introduction
1 Article 62 provides the major procedural device by which the interests of States not
party to proceedings before the ICJ are protected by the Court. The procedure is termed
intervention. Its ‘raison d’être . . . is to enable a third State, whose legal interest might
be affected by a possible decision of the Court, to participate in the main case in order
to protect that interest’.1 Intervention under Article 62 stems from the conviction that
inter-​State proceedings, focused upon the settlement of bilateral disputes,2 may not af-
ford sufficient protection to third States’ interests, despite the well-​established principle
of the relative effect of res judicata. Moreover, Article 62 could ensure and thus enhance
confidence in judicial settlement.
2 Requests for permission to intervene under Article 62 have so far been scarce—​only
fourteen States seised the Court in eleven cases—​and the number of interventions granted
by the Court, four so far,3 is so low that these promises of intervention remain unfulfilled.
On the overall, the Court’s limited case law contains but a few elements of clarification of
the conditions set out for intervention under Article 62 or of the effects of the judgment
on the intervening State.
3 The task of clarification is all the more difficult that Article 62 contains an ‘imposing
array of obscurities, ambiguities and lack of concordance between the two language
versions’,4 deliberately entertained by the drafters of the Statute. In fact, the condi-
tions for intervention were left ‘to be decided as and when they occurred in practice
and in the light of the circumstances of each particular case’.5 This deliberate choice
of the drafters leaves to the Court the cumbersome responsibility of filling in lacunae
in the Statute.

B. Historical Development
I. Antecedents
4 Intervention is a regular procedural device in domestic legal systems,6 but not in inter-​
State proceedings. Unlike the related, but distinct procedure of intervention under

1
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, Judgment, ICJ
Reports (2011), pp. 420 et seq.
2
Wolfrum, ‘Interventions in Proceedings before International Courts and Tribunals: to what Extent May
Interventions Serve the Pursuance of Community Interests?’, in International Courts and the Development of International
Law: Essays in Honour of Tullio Treves (Boschiero et al., eds., 2013), pp. 219–​20; Whaling in the Antarctic, Declaration of
Intervention by New Zealand, Sep. Op. Cançado Trindade, ICJ Reports (2013), pp. 14, 37–​8, paras. 69–​71.
3
See the table published in the ICJ Yearbook (2014–​2015), pp. 142–​3.
4
Shaw, Rosenne’s Law and Practice, vol. III, p. 1497.
5
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 14–​6, paras. 23–​7; see also Continental Shelf (Libya/​Malta), Application by Italy for Permission to
Intervene, ICJ Reports (1984), pp. 3, 27–​8, para. 45.
6
For a comprehensive comparative analysis, see Pulau Ligitan, Application by Philippines for Permission
to Intervention, Sep. Op. Weeramantry, ICJ Reports (2001), pp. 630, 637–​43, paras. 20–​3. Judge ad hoc

miron/chinkin
 Article 62 1689

Article 63, there was no forerunner provision in the Hague Conventions for the Pacific
Settlement of International Disputes of 1899 and 19077 and no existing basis within
international arbitral procedure. The new concept of intervention was not mentioned
in the 1907 project of the Court of Arbitral Justice.8 Rather it was evolved through
various draft plans for the proposed new international court, alongside that of the

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more familiar idea of intervention in proceedings concerning the interpretation of a
convention.
There were various proposals for what subsequently became intervention. Among 5
these, Article 48 of the Plan of the Five Neutral Powers (Norway, Denmark, Sweden,
Holland, and Switzerland) read simply:
Lorsqu’un différend soumis à la Cour touche les intérêts d’un Etat tiers, celui-​ci a le droit
d’intervenir au procès. 9

Article 21 of a Swedish governmental Commission’s draft convention read:

Lorsqu’un différend soumis à la Cour est relatif à une convention internationale générale ou
concerne à d’autres égards les intérêts d’un Etat tiers, qui n’est pas Partie dans le litige, ce dernier
aura le droit d’intervenir dans l’affaire.
La Partie qui a saisi la Cour d’un litige est tenue d’en donner avis à l’Etat qui, aux termes du
premier alinéa du présent article a le droit d’intervenir dans l’affaire. 10

Article 31 of another draft convention on an international judicial organization, prepared

by three committees nominated by Denmark, Norway, and Sweden read:
Lorsqu’une affaire soumise à la Cour porte sur l’interprétation d’une convention internationale
générale ou universelle, ou si elle concerne d’une autre manière les intérêts d’un Etat tiers, ce der-
nier aura le droit d’intervenir dans l’affaire.
Les Etats tiers doivent être avertis par la Partie qui a intenté l’affaire.11

II. The Travaux Préparatoires of the Statute of the Court

The procedural device of intervention under what became Article 62 was introduced 6
into the draft Statute of the PCIJ by the Advisory Committee of Jurists during their
discussions of what is now Article 63.12 Intervention was one of the particular proced-
ural achievements mentioned by Baron Descamps in his summary of the work of the

Weeramantry refers to a comprehensive compilation on the use of intervention in domestic jurisdictions by

Habscheid, ‘Les conditions de l’intervention volontaire dans un procès civil’, submitted to the ICJ in the
Continental Shelf (Tunisia/​Libya) case, Application by Malta for Permission to Intervene, ICJ Reports (1981),
Pleadings, vol. III, pp. 459–​84.
7
Cf. Miron/​Chinkin on Art. 63 MN 3–​7.
8
Report of Mr de Lapradelle, Chairman of the Drafting Committee, Procès-​ Verbaux of the
Proceedings of the Advisory Committee of Jurists (1920), pp. 693–​749. Cf. also Whaling in the Antarctic,
Declaration of Intervention by New Zealand, Sep. Op. Cançado Trindade, ICJ Reports (2013), pp. 14,
27–​8, paras. 35–​7.
9
Draft for the establishment of a Permanent Court of International Justice provided for in Covenant of the
League of Nations (1920), Article 14, Documents Presented to the Committee Relating to Existing Plans for
the Establishment of a Permanent Court of International Justice, pp. 300–​23.
10
Ibid., pp. 236–​51, Draft of a Convention drawn up by a Swedish Governmental Commission in 1919.
11
Ibid.
12
For a summary of the drafting process cf. Continental Shelf (Tunisia/​Libya), Application by Malta for
Permission to Intervene, ICJ Reports (1981), pp. 3, 13–​4, paras. 22–​3.

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 1690 Statute of the ICJ

Advisory Committee.13 Despite its innovatory character, the records of the discussions in
the Advisory Committee of Jurists are ‘inconclusive and apparently garbled’.14
7 The text of what was then Article 60 in the draft Statute put forward by the Advisory
Committee was adopted verbatim as Article 62 of the PCIJ Statute:

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Should a State consider that it has an interest of a legal nature which may be affected by the deci-
sion in the case, it may submit a request to the Court to be permitted to intervene as a third party.
It will be for the Court to decide upon this request.15

Article 62 was initially drafted in French, with the English version being seen as the trans-
lation. The adopted text of Article 62 of the PCIJ Statute read:
Lorsqu’un Etat estime que dans un différend un intérêt d’ordre juridique est pour lui en cause, il
peut adresser à la Cour une requête à fin d’intervention.
La Cour décide.

8 Both versions of the text have remained remarkably consistent since first adopted as
part of the Statute of the PCIJ. Moreover, the Committee of Jurists that prepared the
ICJ Statute in 1945 devoted virtually no discussion to Article 62. The only change in
1945 was the dropping of the words ‘as a third party’ after ‘to be permitted to intervene’
in the English text, words which were absent from the French text of the Statute of the
PCIJ. The phrase was omitted at the initiative of a drafting committee of the Committee
of Jurists preparing the Statute of the ICJ, which considered it to be ‘misleading’. The
Rapporteur indicated that no change was intended in the sense of the provision and that
the change of wording was not deemed to be significant.16 But these words carry weight.
In particular, the ICJ read into them an assumption that ‘a State permitted to intervene
under Article 62 would become a “party” to the case. That was only to be expected as the
English text of Article 62 then spoke specifically of permission to intervene “as a third
party”’.17 And although the words ‘as a third party’ were deleted from the ICJ Statute,
the phrase may still be found in some of the judgments of in the judges’ opinions. More
importantly, despite the deletion of these terms, the Court still maintains the possibility
for an intervener to become a party to the case.18

III. A Persistent Difference of Wording between the French and

English Versions of the Statute
9 The Committee of Jurists omitted to resolve in 1945 another significant difference be-
tween the two official versions of the Statute: while the French version requires from the

13
Address by Baron Descamps, President of the Advisory Committee of Jurists at the Closing Session of the
Committee on 24 July 1920, Procès-​Verbaux of the Proceedings of the Advisory Committee of Jurists (1920),
pp. 752, 754.
14
Rosenne (1993), p. 23.
15
Draft Scheme presented to the Council of the League by the Advisory Committee of Jurists for the insti-
tution of the Permanent Court of International Justice, mentioned in Art. 14 of the Covenant of the League of
Nations, LNOJ, Special Suppl. No. 2, September 1920.
16
UNCIO XIV, p. 613; Continental Shelf (Tunisia/​ Libya), Application by Malta for Permission to
Intervene, ICJ Reports (1981), pp. 3, 15, para. 25; ibid., Sep. Op. Oda, ICJ Reports (1981), pp. 23, 24, para.
3; Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984), pp.
3, 27, para. 44.
17
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 14–​5, para. 24.
18
Cf. infra, MN 120–​127.

miron/chinkin
 Article 62 1691

third State to show that ‘un intérêt d’ordre juridique est pour lui en cause’, the English ver-
sion refers to ‘an interest of a legal nature which may be affected by the Court’s decision in
the case’. The French version is broader than the English one, on more than one account,
since it neither qualifies the ways in which the interest of the third State may be affected
(‘est en cause’), nor does it mention the ‘decision of the Court’ as the source of impact.

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The difference is so striking that in the Land, Island and Maritime Frontier Dispute case, 10
the Chamber took the unusual approach of placing wording from the two texts side by
side in the following passage:
in order to obtain permission to intervene under Article 62 of the Statute, a State has to show an
interest of a legal nature which may be affected by the Court’s decision in the case, or that un intérêt
d’ordre juridique est pour lui en cause—​the criterion stated in Article 62.19

The Chamber did not comment on the difficulties of translation, it simply postulated
that the two versions referred to an equivalent concept. These differences may nonethe-
less trigger important consequences on the appreciation of the risk for the interest to be
affected.20

C. Practice of Intervention under Article 62 of the Statute

Very few applications to intervene under Article 62 have been made before either the 11
PCIJ or the ICJ. The only case where an application to intervene was made before the
PCIJ was:
• Wimbledon (United Kingdom, France, Italy, and Japan v. Germany), by Poland.21
There have been applications to intervene before the ICJ in the following cases:
• Nuclear Tests (Australia and New Zealand v. France), by Fiji; 22
• Continental Shelf (Tunisia/​Libya), by Malta;23
• Continental Shelf (Libya/​Malta), by Italy;24
• Land, Island and Maritime Frontier Dispute (El Salvador/​Honduras), by Nicaragua;25
• Land and Maritime Boundary between Cameroon and Nigeria (Cameroon v. Nigeria),
by Equatorial Guinea;26

19
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 114, para. 52. See also Continental Shelf (Libya/​Malta), Application by
Italy for Permission to Intervene, ICJ Reports (1984), pp. 3, 25, para. 40.
20
Cf. infra, MN 58–​59.
21
Wimbledon, Question of Intervention by Poland, PCIJ, Series A, No. 1, pp. 11 et seq. Intervention was
granted, but under Art. 63 of the Statute.
22
Nuclear Tests (Australia v. France; New Zealand v. France), Application by Fiji for Permission to Intervene,
ICJ Reports (1973), pp. 320 et seq., and pp. 324 et seq., respectively; ibid., Application by Fiji for Permission
to Intervene, ICJ Reports (1974), pp. 530 et seq., and pp. 535 et seq., respectively.
23
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3 et seq.
24
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3 et seq.
25
Land, Island and Maritime Frontier Dispute, Application for Permission to Intervene, Order of 28
February 1990, ICJ Reports (1990), pp. 3 et seq.; Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92 et seq.
26
Land and Maritime Boundary, Order of 21 October 1999, ICJ Reports (1999), pp. 1029 et seq.

miron/chinkin
 1692 Statute of the ICJ

• Request for an Examination of the Situation in Accordance with Paragraph 63 of the

Court’s Judgment of 20 December 1974 in the Nuclear Tests (New Zealand v. France)
Case (New Zealand v. France), by Australia, the Solomon Islands, the Federated States
of Micronesia, the Marshall Islands, and the Samoa Islands.27 The last four States also
made declarations of intervention under Article 63;

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• Sovereignty over Pulau Ligitan and Pulau Sipadan (Indonesia/​Malaysia), by the Philippines;28
• Territorial and Maritime Dispute (Nicaragua v. Colombia), by both Costa Rica29 and
Honduras;30
• Jurisdictional Immunities of the State (Germany v. Italy), by Greece.31
12 In some other cases there have been indications that a State has been considering
intervention, or has decided against doing so. For example, in the Eastern Greenland
case, Iceland withdrew a request to intervene.32 In the Pakistani POW case,33 Afghanistan
indicated that it had an interest in Pakistan’s claims relating to State succession,34 but
made no formal request to intervene before the case was removed from the General List.
Rosenne recounts that the agents in the Aerial Incident of 27 July 1955 cases examined
the possibility of each applicant State (Israel, United Kingdom, and the United States)
seeking to intervene under Article 62 in each other case.35 Finally, Colombia appears to
have envisaged to intervene in the Caribbean Sea Delimitation case,36 but the Honduras
precedent left it with little prospects for success and finally decided not to.
13 The brief list of cases in which an application to intervene has been made or considered
shows that the procedure has been little used. States have not come to ‘regard interven-
tion as a predictable contingency of international life’37 and:
What might well have been expected, at the time the Court’s Statute was adopted, to grow into a sub-
stantial branch of international jurisprudence, has thus turned out to be extremely limited in its growth.38

14 The cases where a request to intervene has been granted are even more limited. There
was no successful request to intervene under Article 62 before the PCIJ. Poland’s request,

27
Request for an Examination of the Situation in Accordance with Paragraph 63 of the Court’s Judgment of 20
December 1974 in the Nuclear Tests (New Zealand v. France) Case, Order of 22 September 1995, ICJ Reports
(1995), pp. 288, 306, para. 67. The Court decided, by the same Order, on the main case, on the request for
provisional measures and on the applications to intervene.
28
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575 et seq.
29
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348 et seq.
30
Ibid., Application by Honduras for Permission to Intervene, ICJ Reports (2011), pp. 420 et seq.
31
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
ICJ Reports (2011), pp. 494 et seq.
32
Even in the absence of a request to intervene, the PCIJ indicated in its judgment that the extent of a claim
of sovereignty by another power was a factor to be taken into account; Eastern Greenland, Judgment, PCIJ,
Series A/​B, No. 53, pp. 21, 46; cf. the letters from the Prime Minister of Iceland to the Registrar of 19 August
and 25 October 1932, PCIJ, Series C, No. 67, pp. 4081–​2.
33
Pakistani POW, Provisional Measures, ICJ Reports (1973), pp. 328 et seq.
34
The Minister for Foreign Affairs of Afghanistan stated in a letter to the President of the Court (12 August
1973) that if the decision of the Court ‘would involve unequal treaties imposed by Britain on Afghanistan, and
be in variance with our national interests, then Afghanistan, in accordance with the Statute . . . will resort to
peaceful actions in order to defend its legitimate interests’ (Pakistani POW, Pleadings, p. 168).
35
Rosenne (1993), pp. 7–​8.
36
Caribbean Sea Delimitation and Islas Portillos, CR 2017/​10, 6 July 2017, pp. 45–​6, para. 38 (Brotons).
37
Elias (1983), p. 91.
38
Cf. Pulau Ligitan, Application by the Philippines for Permission to Intervene, Sep. Op. Weeramantry, ICJ
Reports (2001), pp. 630, 631, para. 4.

miron/chinkin
 Article 62 1693

in the Wimbledon case, was made on the basis that the cargo of the vessel was consigned
to the Polish Naval Base at Danzig and thus it had a legal interest in the decision in the
case.39 However, Poland also referred to Article 380 of the Treaty of Versailles, concerning the
Kiel Canal, which led the British agent to suggest that the intervention would more prop-
erly come under Article 63, a suggestion that was accepted by Poland and approved by the

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Court.40
Before the ICJ, there have been three successful requests to intervene under Article 62, all 15
others being dismissed. Fiji’s request in the Nuclear Tests cases41 and those of Australia, the
Solomon Islands, the Federated States of Micronesia, the Marshall Islands, and the Samoa
Islands in the 1995 Request for an Examination of the Situation in Accordance with Paragraph
63 of the Court’s Judgment of 20 December 1974 in the Nuclear Tests (New Zealand v. France)
Case were all dismissed when the main case was found to be inadmissible. The requests of
Malta in the Continental Shelf (Tunisia/​Libya) case, of Italy in the Continental Shelf (Libya/​
Malta) case, of the Philippines in the Pulau Ligitan case and of both Costa Rica and Honduras
in the Territorial and Maritime Dispute were all rejected. Nicaragua’s request to intervene in
the Land, Island and Maritime Frontier Dispute case was accepted by a Chamber of the Court
and Equatorial Guinea’s request in the Land and Maritime Boundary case was accepted by the
full Court, as was that of Greece in the Jurisdictional Immunities of the State case.

D. Characteristics of Intervention under Article 62

I. Intervention as Incidental Proceedings
Intervention, either under Article 62 or Article 63 of the Statute, applies only to conten- 16
tious proceedings.42 It is available only to States. A provision allowing the International
Labour Office, or other international institutions to request intervention was rejected
by the sub-​committee of the Third Committee of the First Assembly of the League of
Nations.43 This differentiates intervention from amicus curiae briefs, under the forms al-
lowed by Article 34, para. 2 of the Statute for contentious proceedings and by Article 66,
para. 2 for advisory opinions.44
Intervention has consistently been characterized as ‘incidental to the proceedings’45 17
which are already before the Court.46 Logically, the provisions of the 1978 Rules of Court
concerning intervention (Articles 81, 83–​85) appear in Part III, headed ‘Proceedings in

39
Wimbledon, Application by the Polish Government to Intervene, PCIJ, Series A, No. 1, pp. 9–​10.
40
Ibid., Observations on the Part of the Government of His Britannic Majesty in pursuance of Rule 59 of
the Rules of the Court on the Subject of the Polish Application to be allowed to intervene in the Wimbledon
case, Series C, No. 3, vol. I, pp. 106–​8.
41
Nuclear Tests (Australia v. France; New Zealand v. France), Application by Fiji for Permission to Intervene,
ICJ Reports (1974), pp. 530 et seq., and pp. 535 et seq.
42
In Acquisition of Polish Nationality, Advisory Opinion, PCIJ, Series B, No. 7, pp. 5 et seq., Romania was
advised that Art. 62 and 63 were inapplicable to the advisory jurisdiction of the PCIJ.
43
Records of First Assembly, Committee I, pp. 400, 499–​500, 537.
44
Cf. Dupuy/​Hoss on Art. 34 MN 1–​5, 39–​41 and Paulus on Art. 66 MN 12–​18; Sands/​Mackenzie,
‘International Courts and Tribunals, Amicus Curiae’, Max Planck EPIL.
45
Haya de la Torre, Judgment, ICJ Reports (1951), pp. 71, 76; Nicaragua, Jurisdiction and Admissibility,
ICJ Reports (1984), pp. 392, 425, para. 74; Land, Island and Maritime Frontier Dispute, Application for
Permission to Intervene, Order of 28 February 1990, ICJ Reports (1990), pp. 3, 4; ibid., Application by
Nicaragua for Permission to Intervene, Judgment, ICJ Reports (1990), pp. 92, 127–​8, para. 84.
46
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 134, para. 98.

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 1694 Statute of the ICJ

Contentious Cases, Section D, Incidental Proceedings’.47 Consequently, Article 84 of

the Rules affords ‘litigants an important protection against protracted uncertainty’48 by
requiring that an application to intervene be dealt with ‘as a matter of priority’, although
the Court has a discretion to act otherwise.
18 Several important consequences arise from the incidental nature of intervention. First,

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it ensures that the case is not transformed into a new dispute, a ‘different case with dif-
ferent parties’.49 This aspect would be discussed in greater detail in relation to the object
of intervention.50
19 The second consequence of the incidental nature of intervention relates to the court
competent to examine the admissibility of the applications made under Article 62 and
63 of the Statute. It is a general principle of adjudication that the court competent for
the main proceedings is also competent for deciding on incidental matters.51 Accessorium
sequitur principale. In Land, Island and Maritime Frontier Dispute, the ICJ clarified that
the principle applied also when the dispute was submitted to a chamber. In that case,
Nicaragua’s claim to have its application considered by the full Court, and not by the
chamber dealing with the merits of the case, was rejected by the plenary:
[I]t is for the tribunal seised of a principal issue to deal also with any issue subsidiary thereto; . . . a
chamber formed to deal with a particular case therefore deals not only with the merits of the case,
but also with incidental proceedings arising in that case.52

19 Finally, the question arises as to whether an incidental proceeding can be introduced in

relation to other incidental proceedings like the preliminary objections or the provisional
measures. The Court case law tends to provide a negative answer to that. On three oc-
casions, the Court rejected interventions at an incidental phase (submitted either under
Article 63 or under Article 62). But each of these cases must be resituated in their own
context.
20 In the Nuclear Tests cases, Fiji’s application to intervene was made on the basis of
Article 62 of the Statute and related to the merits of the case. It was deposited on 18
May 1973, nine days after the applications instituting proceedings, and two days after
France had contested the Court’s jurisdiction.53 By a first order, the ICJ deferred con-
sideration of Fiji’s request to intervene until it had pronounced on France’s objections

47
Insisting upon the incidental character of intervention, Torres Bernárdez, Rec. des Cours (1995-​VI),
pp. 270–​1.
48
Lachs, ‘The Revised Procedure of the International Court of Justice’, in Essays on the Development
of the International Legal Order in Memory of Haro F. Van Panhuys (Kalshoven et al., eds., 1980),
pp. 21–​5 2, 40.
49
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 134, para. 98.
50
Cf. infra, MN 77–​83.
51
Obviously, this general principle applies in the absence of contrary provisions in the instruments which
govern jurisdiction. For instance, Art. 290, para. 5 UNCLOS (10 December 1982, 1833 UNTS 3) provides
that ITLOS has jurisdiction to decide on provisional measures pending the constitution of an Annex VII ar-
bitral tribunal.
52
Land, Island and Maritime Frontier Dispute, Application for Permission to Intervene, Order of 28
February 1990, ICJ Reports (1990), pp. 3, 4.
53
Nuclear Tests (Australia v. France; New Zealand v. France), Application by Fiji for Permission to Intervene,
ICJ Reports (1973), pp. 320 et seq. and pp. 324 et seq. The application was rapidly filed in the hope that the
Court would allow Fiji to participate at the hearings on provisional measures (ibid., Application for Permission
to Intervene by Fiji, pp. 149, 151).

miron/chinkin
 Article 62 1695

to jurisdiction and admissibility,54 and by a second order, it held that the application
‘lapsed’,55 on grounds that the main proceedings ‘no longer [had] any object’.56 The two
orders contain two singularly Delphic statements on the link between the main and
the incidental proceedings. In the first, the Court considered that ‘the application of
Fiji by its very nature presupposes that the Court has jurisdiction to entertain the dis-

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pute between New Zealand [Australia] and France and that New Zealand’s [Australia’s]
Application against France in respect of that dispute is admissible’.57 The use of the
term ‘by nature’ would seem to refer to the proceedings of intervention, not to the
content or object of Fiji’s application. Thus, a request to intervene at the jurisdictional
stage, would be premature, because intervention presupposes that the Court has juris-
diction. However, beyond this textual argument, there is nothing in the order or in the
judges’ opinions to sustain this view.58 When it found that ‘the claim of New Zealand
no longer [had] any object’,59 the Court logically concluded in its second order that ‘in
consequence there [would] no longer be any proceedings before the Court to which the
Application for permission to intervene could relate’.60 The treatment of Fiji’s request
to intervene means two things: first, that an intervention based on a legal interest re-
lating to the merits shall be considered as premature at the jurisdictional stage; second,
a request to intervene cannot withstand dismissal of the main case. But this precedent
should not be interpreted as rejecting at large the possibility of intervention on jurisdic-
tional issues at the jurisdictional stage.
The Court’s order in the Nicaragua case confirms that the applications dealing with the 21
merits are premature at the jurisdictional stage:61
[T]‌he Declaration of Intervention of the Republic of El Salvador, which relates to the present phase
of the proceedings [the preliminary objections], addresses itself also in effect to matters, including
the construction of conventions, which presuppose that the Court has jurisdiction to entertain the
dispute.62

Consequently, the Court concluded that ‘the declaration . . . is inadmissible inasmuch as

it relate[d]‌to the current phase of the proceedings between Nicaragua and the United
States’.63 The Court did not opt for deferring consideration, as it did in Fiji’s case, be-
cause El Salvador made clear that its intention was to intervene at the jurisdictional
stage, though it left open the possibility to intervene on the merits too. This conclusion
on admissibility being provisional, the Court reiterated it, with specific reference to the

54
Ibid., Application by Fiji for Permission to Intervene, ICJ Reports (1973), pp. 320 et seq., and pp. 324
et seq.
55
Nuclear Tests (New Zealand v. France), Application by Fiji for Permission to Intervene, ICJ Reports
(1974), pp. 535, 536.
56
Ibid., p. 535.
57
Nuclear Tests (Australia v. France; New Zealand v. France), Application by Fiji for Permission to Intervene,
ICJ Reports (1973), pp. 320 et seq. and pp. 324 et seq.
58
The judges having appended statements insisted upon the lack of jurisdictional link (cf. infra, MN 95).
59
Nuclear Tests (New Zealand v. France), Application by Fiji for Permission to Intervene, ICJ Reports
(1974), pp. 535 et seq.
60
Ibid.
61
Since El Salvador attempted to intervene under Art. 63 of the Statute, the case is analysed in more detail
in Miron/​Chinkin on Art. 63 MN 43–​50.
62
Nicaragua, Declaration of Intervention of the Republic of El Salvador, ICJ Reports (1984), pp. 215, 216.
63
Ibid.

miron/chinkin
 1696 Statute of the ICJ

‘current phase of the proceedings’ in its judgments on jurisdiction and admissibility64 and
on the merits.65
22 Finally, in the Request for an Examination of the Situation in Accordance with Paragraph
63 of the Court’s Judgment of 20 December 1974 in the Nuclear Tests (New Zealand
v. France) Case, Australia, the Federated States of Micronesia, the Marshall Islands, the

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Samoa Islands, and the Solomon Islands, applied to intervene in New Zealand’s request
for provisional measures. The intervening States argued that Article 62 does not limit the
phase of proceedings when such an application may be made and that, in the particular
circumstances of the case, the provisional measures phase might be the only time a re-
quest to intervene could have any practical effect.66 Like for the 1974 case,67 the Court’s
dismissal of New Zealand’s request precluded any decision on intervention.
24 Rosenne and Shaw also consider that there is not in the Statute an absolute bar from
introducing an application to intervene on jurisdictional issues,68 provided the admissi-
bility requirements are respected. Fiji’s and El Salvador’s application related not to the
subject-​matter of the proceedings on jurisdiction, but to the merits. As such, the object
of their intervention69 was not aligned with the subject-​matter of the proceedings to
which they purported to relate. It may be that the conditions for admissibility applied
to the interlocutory stage are easier to satisfy under Article 63 than under Article 62.70
There is however one textual argument to support the inadmissibility of application for
interventions at the preliminary or provisional measures stage and it may be drawn from
the requirement that the interest of the third State must be at risk of being affected by
‘the decision in that case’. In the context of intervention, the Court tends to interpret
these terms as referring to the judgment on the merits, as will further be seen. 71 If this re-
striction is confirmed, in that case, it may indeed be difficult to make applications under
Article 62 at an interlocutory stage.

II. Intervention as Statutory Jurisdiction

25 The question whether jurisdiction over intervention is based on States’ consent has been
a most controversial issue.72 When a Chamber of the Court finally resolved it in 1990, in
the Land, Island and Maritime Frontier Dispute case, it also made the important clarifica-
tion that intervention was founded on the Statute:
The competence of the Court in this matter of intervention is not, like its competence to hear and
determine the dispute referred to it, derived from the consent of the parties to the case, but from

64
Ibid., Jurisdiction and Admissibility, ICJ Reports (1984), pp. 392, 396, para. 6.
65
Ibid., Merits, ICJ Reports (1986), pp. 14, 17, para. 7.
66
Request for an Examination of the Situation in Accordance with Paragraph 63 of the Court’s Judgment of 20
December 1974 in the Nuclear Tests (New Zealand v. France) Case, Order of 22 September 1995, ICJ Reports
(1995), pp. 288, 301, paras. 24–​5, 41, and pp. 306–​7, para. 67. The Applications of the Marshall Islands,
Micronesia, Samoa, and the Solomon Islands were all made both under Arts. 62 and 63 of the Statute and in
similar terms (ibid., p. 292, para. 11).
67
Cf. supra, MN 20.
68
For a contrary view, see Shaw, Rosenne’s Law and Practice, vol. III, pp. 1529–​35.
69
On the requirements relating to the object of the intervention, cf. infra, MN 75–​90.
70
Nicaragua, Declaration of Intervention of the Republic of El Salvador, Diss. Op. Schwebel, ICJ Reports
(1984), pp. 223, 234.
71
Cf. infra, MN 58–​59.
72
Cf. infra, MN 91–​102.

miron/chinkin
 Article 62 1697
the consent given by them, in becoming parties to the Court’s Statute, to the Court’s exercise of its
powers conferred by the Statute. 73

The Chamber added: It is ‘acceptance of the Statute [which] entails acceptance of the
competence conferred on the Court by Article 62’.74 Therefore, intervention can be con-

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sidered as an example of statutory jurisdiction, alongside interpretation and revision,
with the difference however that these two forms lead to the introduction of new cases,
identified as such on the General List, whereas intervention is an incidental proceeding.
Some authors raise the question whether intervention is, ratione personae, open only 26
to parties to the Statute. They consider that since Articles 62 and 63 mention ‘a State/​
every State’ in general, there is no such particular restriction.75 But, as a form of statutory
jurisdiction, intervention rests upon the acceptance of the Statute. It is then logical that
both forms of intervention (under Articles 62 and 63) should be open only to parties to
the Statute or to States having otherwise accepted the Statute according to its Article 35,
para. 2.76
Since the ratification of the Statute gives to the Court jurisdiction over intervention, 27
the conditions set out by the relevant provisions of the Statute and of the Rules constitute
conditions for the admissibility of the request, and not conditions for jurisdiction.77 The
Court pays more and more attention to the distinction between the two. An objection to
admissibility ‘consists in the contention that there exists a legal reason, even when there
is jurisdiction, why the Court should decline to hear the case, or more usually, a specific
claim therein’.78 In Certain Questions of Mutual Assistance in Criminal Matters, the Court
added that ‘in determining the scope of the consent expressed by one of the parties, the
Court pronounces on its jurisdiction and not on the admissibility of the application’.79
In intervention proceedings, this insistence upon admissibility as opposed to jurisdiction
highlights the will to disconnect intervention from States’ consent.

III. The Margin of Appreciation of the Court

Even if jurisdiction over intervention is established by the Statute, the Rules of the Court 28
systematically organize a separate, preliminary proceeding, dedicated to the appreciation
of the admissibility of the applications made under Article 62 and 63. This means that
neither form of intervention is as of right. The Court’s margin of appreciation is however
different under the two provisions. Even if intervention under Article 62 has been termed
‘discretionary/​discretional intervention’, the Court has asserted that it has no discretion

73
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 133, para. 96.
74
Ibid.
75
Quintana, ICJ Litigation, pp. 852–​3; Shaw, Rosenne’s Law and Practice, vol. III, pp. 1527–​8; Chinkin in
the second edition of this Commentary (Art. 62 MN 7).
76
Cf. also Zimmermann on Art. 35 MN 38.
77
As the Court put it, ‘the task entrusted to it by that paragraph is to determine the admissibility or other-
wise of the request by reference to the relevant provisions of the Statute’ (Continental Shelf (Tunisia/​Libya),
Application by Malta for Permission to Intervene, ICJ Reports (1981), pp. 3, 12, para. 17.
78
Question of the Delimitation of the Continental Shelf between Nicaragua and Colombia beyond 200 Nautical
Miles from the Nicaraguan Coast, Preliminary Objections, ICJ Reports (2016), pp. 100, 123, para. 48, quoting
Croatian Genocide, Preliminary Objections, ICJ Reports (2008), pp. 412, 456–​7, para. 120; in the same sense,
see Oil Platforms, Merits, ICJ Reports (2003), pp. 161, 177, para. 29.
79
Certain Questions of Mutual Assistance in Criminal Matters, Judgment, ICJ Reports (2008), pp. 177, 200,
para. 48.

miron/chinkin
 1698 Statute of the ICJ

to reject a request solely on policy grounds. When the article was drafted, Lord Phillimore
proposed the inclusion of an explicit discretion that the Court could grant the request ‘if
it sees fit’.80 This was rejected. Thus, the Court does not have the faculty to reject inter-
vention if the statutory conditions are met.81 Its margin of discretion rests within the
appreciation of the conditions stipulated in Article 62,82 but it remains important due

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to the vagueness of the relevant provisions. This being said, the Court considers that ad-
mission or rejection of intervention is guided not only by compliance with the statutory
conditions, but also by the principle of the sound administration of justice:
It is for the Court, responsible for safeguarding the proper administration of justice, to decide
whether the condition laid down by Article 62, para. 1, has been fulfilled.83

The reference to the principle of the sound administration of justice echoes the functions
of intervention, which aim at informing the Court on the factual and legal context of
the dispute submitted to it, thus providing it with all the necessary elements for deciding
it.84 It is also reminiscent of the fact that, as all incidental powers, the admission of inter-
vention is deemed necessary or appropriate for the Court to discharge its principal mis-
sion (that of deciding the dispute submitted to it). However, the reference to the sound
administration of justice also supports the vision according to which the Court decides
to grant or not an intervention under Article 62 not only on legal grounds, but also ac-
cording to considerations of opportunity.85 This being said, the conditions for the admis-
sibility of an application under Article 62 are sufficiently vague to leave to the Court a
large margin of appreciation.86 In particular, since the interest of a legal nature of the third
State must be at risk of being affected by the decision on the merits, the Court can—​and
does—​rely on a its own engagement to protect the third State’s interests at the merits
stage in order to reject the application.87
29 The degree of discretion enjoyed by the Court under Article 62 may also be appreci-
ated in light of the attitude of the parties. Since intervention does not rest on parties’ con-
sent, their objection is not enough to dismiss the application: ‘opposition of the parties

80
Lord Phillimore proposed that if ‘a State considers that a dispute submitted to the Court affects its inter-
ests, it may request to be allowed to intervene; the Court shall grant permission if it thinks fit’. Procès-​Verbaux
of the Proceedings of the Advisory Committee of Jurists (1920), p. 593.
81
It has been argued that the concept of a ‘request’ suggests potential refusal, despite compliance with
the stipulated criteria (Fitzmaurice, ‘The Law and Procedure of the International Court of Justice, 1951–​
1954: Questions of Jurisdiction, Competence and Procedure’, BYIL 34 (1958), pp. 1–​161, 127).
82
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 12, para. 17; Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ
Reports (1984), pp. 3, 8–​9, para. 12; Territorial and Maritime Dispute, Application by Honduras for Permission
to Intervene, ICJ Reports (2011), pp. 420, 434, para. 36.
83
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 434, para. 36, quoting Continental Shelf (Tunisia/​Libya), Application by Malta for Permission
to Intervene, ICJ Reports (1981), pp. 3, 12, para. 17. See also Continental Shelf (Libya/​Malta), Application by
Italy for Permission to Intervene, ICJ Reports (1984), pp. 3, 12, paras. 17–​8; Territorial and Maritime Dispute,
Application by Costa Rica for Permission to Intervene, ICJ Reports (2011), pp. 348, 358, para. 25.
84
Cf. Kolb, ‘Le principe de la “bonne administration de la justice” dans la jurisprudence internationale’,
L’Observateur des Nations Unies 27 (2009), pp. 5–​21, 12. Cf also infra, MN 84–​85.
85
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, Diss. Op.
Abraham, ICJ Reports (2011), pp. 447, 450, para. 12; Territorial and Maritime Dispute, Application by Costa
Rica for Permission to Intervene, ICJ Reports (2011), Diss. Op. Cançado Trindade and Yusuf, pp. 402, 409,
paras. 1, 15.
86
Cf. infra, MN 44–​102.
87
Cf. infra, MN 72–​74.

miron/chinkin
 Article 62 1699

to a case is, though very important, no more than one element to be taken into account
by the Court’.88 It remains unclear however on what bases and to what extent the par-
ties’ attitude should influence the Court’s assessment of the admissibility of intervention.
Apart from the fact that the Rules of the Court reserve a different procedural treatment
to unopposed applications,89 it remains that, with the exception of Nicaragua’s applica-

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tion in the Land, Island and Maritime Frontier Dispute, in the other two cases when the
Court declared admissible the applications for permission to intervene, there was no
objection from the parties to the dispute.90 The least one could say is that, though not
decisive, the absence of an objection from the parties certainly facilitates the acceptance
of intervention.91

IV. Intervention and the Indispensable Third Party

The absence of a third party may prevent the Court from adjudicating the case where that 30
party has rights in the very subject-​matter of the case, indicating the close connection
between intervention under Article 62 and the principle of the so-​called indispensable
third party. However, several elements help distinguishing the two hypotheses: the indis-
pensable party is the one whose rights constitute the very-​subject matter of the case sub-
mitted to the Court, while for intervention, only the legal interests need to be presumably
affected. Unlike intervention, the indispensable third party rule is not provided for within
the Statute of the Court, but rests upon the principle of consent.92 Accordingly, the ab-
sence of the indispensable third party prevents the Court from exercising jurisdiction.
In Monetary Gold, it was contended that Albania might have intervened, and that there 31
was nothing in the Statute to prevent proceedings from continuing when a third State
which would be entitled to intervene refrained from doing so.93 The Court concluded
that a third State has a choice whether or not to intervene and that if it chooses not to it
is protected by Article 59 of the Statute.94 Since Albania’s rights were the subject-​matter
of the dispute, the proceedings could not be continued in its absence.95
In the Land, Island and Maritime Frontier Dispute case, Nicaragua explicitly linked the 32
indispensable third party principle with intervention. Nicaragua argued that Monetary
Gold meant that the case could not be heard without its participation, i.e., that its failure
to intervene could deprive the Court of its jurisdiction bestowed by special agreement be-
tween the parties. The Chamber agreed that if Nicaragua’s interests did indeed constitute

88
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 133, para. 96, quoting Continental Shelf (Libya/​Malta), Application by
Italy for Permission to Intervene, ICJ Reports (1984), pp. 3, 28, para. 46.
89
See Art. 84, para. 2 of the Rules; cf. infra MN 118–​119.
90
See Land and Maritime Boundary, Order of 21 October 1999, ICJ Reports (1999), pp. 1029, 1033–​4,
paras. 9–​10; Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to
Intervene, ICJ Reports (2011), pp. 494, 496, para. 6.
91
Criticizing the influence upon the Court of the attitude of the parties, see Territorial and Maritime
Dispute, Application by Honduras for Permission to Intervene, Diss. Op. Donoghue, ICJ Reports (2011), pp.
471, 490–​1, para. 56.
92
Land and Maritime Boundary, Judgment, ICJ Reports (2002), pp. 303, 421, para. 238. Cf. also Tomuschat
on Art. 36 MN 21–​25 and Brown on Art. 59 MN 60–​67.
93
Monetary Gold, Judgment, ICJ Reports (1954), pp. 19, 32.
94
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 114–​5, para. 54.
95
The Monetary Gold principle was applied in East Timor, Judgment, ICJ Reports (1995), pp. 90 et seq. to
prevent the Court from deciding the case in the absence of Indonesia.

miron/chinkin
 1700 Statute of the ICJ

part of the ‘very subject matter of the decision’ it would doubtless justify intervention
under Article 62 ‘which lays down a less stringent criterion’.96 However, it found that
while Nicaragua had a legal interest in the case, this did not form the very subject-​matter
of the case. The Chamber therefore did not have to determine whether it would have
been able to continue the case without Nicaragua’s participation.97

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33 The absence of the indispensable third party is all the more an obstacle to the Court’s
exercise of jurisdiction that, to the difference of ‘[n]‌ational courts, [which] have more
often than not the necessary power to order proprio motu the joinder of third parties who
may be affected by the decision to be rendered . . . on the international plane the Court
has no such power’.98 Intervention is a ‘procedural faculty’,99 not an obligation of the
would-​be intervener. This being said, the Court, or some of its members, can of course
‘draw the attention of third States to the possible impact that its future judgment on the
merits may have on their interests’, leaving it to such third States to decide whether or
not to request intervention.100 In the Barcelona Traction case, Judge Fitzmaurice suggested
that Canada could have been asked to intervene to cast further light on the status of the
corporation.101 In Land and Maritime Boundary, the Court stated in its judgment on the
preliminary objections that Equatorial Guinea’s and to São Tomé and Principe’s interests
may be affected by the decision on the merits. It added that ‘[w]hether such third States
would choose to exercise their rights to intervene in these proceedings pursuant to the Statute
remained to be seen’.102 Following this virtual invitation to intervene, Equatorial Guinea
chose to do so, the parties did not object, and the full Court unanimously accepted
Equatorial Guinea’s request. São Tomé and Principe did not request intervention.

E. Requirements for Intervention under Article 62

34 The Rules of the Court provide for more detailed substantive and formal conditions for
the admissibility of an application for permission to intervene and thus clarify the vague-
ness of Article 62. ‘Since the Rules cannot add to or modify the effect of the Statute, it
has to be assumed that [the] additional items of information are required only to enable
the Court more effectively to appreciate whether the statutory requirements of interven-
tion are fulfilled.’103

96
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 116, para. 56.
97
Ibid., p. 122, para. 73.
98
Nauru, Preliminary Objections, ICJ Reports (1992), pp. 240, 260, para. 53. See also Land, Island and
Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene, Judgment, ICJ Reports
(1990), pp. 92, 134–​5, para. 99, citing Continental Shelf (Libya/​Malta), Application by Italy for Permission to
Intervene, ICJ Reports (1984), pp. 3, 25, para. 40 and Nicaragua, Jurisdiction and Admissibility, ICJ Reports
(1984), pp. 392, 431, para. 88; East Timor, Judgment, ICJ Reports (1995), pp. 90, 101, para. 26.
99
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 28, para. 46.
100
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 433, para. 34.
101
‘[T]‌he intervention of the Canadian Government under Article 62 . . . should have been sought, in order
that its views might be made known’. Barcelona Traction, Merits, ICJ Reports (1970), Sep. Op. Fitzmaurice,
ICJ Reports (1970), pp. 65, 80, para. 28.
102
Land and Maritime Boundary, Preliminary Objections, ICJ Reports (1998), pp. 275, 324, para. 116,
emphasis added in ibid., Order of 21 October 1999, ICJ Reports (1999), pp. 1029, 1030, para. 2.
103
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, Diss. Op. Jennings,
ICJ Reports (1984), pp. 148, 152, para. 12.

miron/chinkin
 Article 62 1701

I. Evolution of the Rules of Court

Unlike the text of Article 62, the relevant Rules of Court have been changed a number 35
of times.104 The changes have not resolved the ambiguities and uncertainties. One of
the areas that successive Rules of Court have addressed is what the State party must

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include in a request to intervene. The initial draft of the 1922 Rules of Court stated in
its Article 48:
A party intervening under Article 62 of the Court Statute shall take part in the proceedings as a
joint party. A party wishing to intervene under the terms of this Article shall address a written ap-
plication to the Registrar. The application shall contain:
1) the designation of the case;
2) a statement of the facts justifying intervention;
3) a list of annexes.105

This draft also made provision for the President to decide upon the request, ‘if the 36
Court is not in session’. Whether the State requesting intervention should have to provide
more details to show that it had complied with Article 62 was controversial. A number of
questions concerned the Advisory Committee of Jurists. They were identified in a ques-
tionnaire that accompanied the proposed draft. Part III, para. 7 concerned intervention.
The questions raised were:
1. Have third States interested in a case the right of intervention only when the original
parties have accepted the compulsory jurisdiction of the Court?
2. Is there any difference in this regard between Article 62 and Article 63 of the
Statute?
3. What principle should the Court adopt, when several parties are taking joint action
in a case before the Court, in deciding which party should have the right to appoint
a judge of its own nationality, in conformity with Article 31 of the Statute?106
In the extensive discussions on these questions in the drafting committee it became ap-
parent that there was no agreement on these and other such central issues. In light of the
lack of consensus a ‘meagre’107 Rule was adopted in 1922 that avoided these controversial
issues, leaving them to be decided by the Court as they arose.108
Article 59 of the 1922 Rules of Court, as finally adopted, read:
The application referred to in the previous Article (An application for permission to intervene
under the terms of Article 62) shall contain:
1) a specification of the case in which the applicant desires to intervene;
2) a statement of law and of fact justifying the intervention;
3) a list of the documents, in support of the application; these documents shall be attached.109

The Article was not amended in 1926 or 1931. In 1936, it was renumbered as Article
64 and slightly reworded but the requirements for an application to intervene remained

104
Cf. Rosenne (1993), pp. 39–​78; Shaw, Rosenne’s Law and Practice, vol. III, pp. 1511–​20.
105
Rules of Court, Draft prepared by the Secretariat, PCIJ, Series D, No. 2, pp. 253, 266.
106
Questions to be submitted for discussion at a full meeting of the Court on 7 February 1922, ibid.,
pp. 289–​91.
107
Lachs, supra, fn. 48, p. 39.
108
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 14, para. 23.
109
Preparation of the Rules of Court of January 30th, 1922, PCIJ, Series D, No. 2, p. 573.

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 1702 Statute of the ICJ

the same. Article 64, para. 2 (a) of the 1945 Rules of Court required the State re-
questing intervention to provide a ‘description of the case’ but otherwise repeated the
earlier Rules.
37 It was not until the 1978 Rules of Court that requirements were introduced for much
greater specificity in the form and contents of a request to intervene. Article 81 of the

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1978 Rules of Court reads as follows:
1. An application for permission to intervene under the terms of Article 62 of the Statute, signed
in the manner provided for in Article 38, para. 3, of these Rules, shall be filed as soon as
possible, and not later than the closure of the written proceedings. In exceptional circum-
stances, an application submitted at a later stage may however be admitted.
2. The application shall state the name of an agent. It shall specify the case to which it relates and
shall set out:
(a) the interest of a legal nature which the state applying to intervene considers may be af-
fected by the decision in that case;
(b) the precise object of the intervention;
(c) any basis of jurisdiction which is claimed to exist as between the State applying to inter-
vene and the parties to the case.
3. The application shall contain a list of the documents in support, which documents shall be
attached.

Appointment and naming of an agent were not specified in the articles on interven-
tion in the earlier Rules of Court, as all provisions on agents were grouped together.110
Even if some of its paragraphs may look outdated, Rule 81 has not been amended
ever since.

II. Procedural Conditions
38 Article 81 establishes procedural conditions for the admissibility of intervention: the
request to intervene must be made through an ‘application’. The term used is different
from a request under Article 63, which is made via a ‘declaration’, but this difference
is merely terminological, the procedural requirements being very similar. As a matter
of form, the application ‘shall state the name of the agent’ (Article 81, para. 2),
and ‘contain a list of documents in support, which documents shall be attached’
(Article 81, para. 3).
39 The procedural requirement which led to some discussion concerns the timing within
which an application can be made. The deadline for submitting an application under
Article 62 varied throughout the different versions of the Rules of Court.
40 Article 58 of the 1922 Rules of Court stated:
An application for permission to intervene under the terms of Article 62 of the Statute, must
be communicated to the Registrar at latest before the commencement of the oral proceedings.
Nevertheless the Court may, in exceptional circumstances, consider an application submitted
at a later stage.111

This article was not changed in 1926 or 1931. In 1936 it was renumbered as Article 64,
para. 1, but remained in essence the same.112 The same time specification was maintained

110
Rosenne (1993), p. 67.
111
Preparation of the Rules of Court of January 30th, 1922, PCIJ, Series D, No. 2, pp. 560, 572–​3.
112
Art. 64, para. 1 of the 1936 Rules of Court stated that the application ‘shall be filed’ in place of the ‘must
be communicated’ of the earlier version (emphasis added).

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 Article 62 1703

with the adoption of the 1945 Rules of Court of the ICJ. Article 64 of the Rules re-
quired the application ‘to be filed in the Registry’ rather than just communicated to the
Registrar. In 1972, Article 64 was again renumbered, to Article 69, but again without
changing the time requirement.
By contrast, Article 81, para. 1 of the 1978 Rules of Court changed the relevant time

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limit, since:
An application for permission to intervene . . . shall be filed as soon as possible, and not later than the
closure of the written proceedings. In exceptional circumstances, an application submitted at a later
stage may however be admitted. (emphasis added)

The Rules allow some discretion for an application after the closure of the written pro-
ceedings but the Court has not indicated what might constitute ‘exceptional circum-
stances’ for these purposes.
States submit applications very late, which is detrimental to the ‘orderly and exped- 41
itious’ progress of proceedings necessary to the sound administration of justice.113 The
Court may at times point out to this disruptive effect, but no application has been dis-
missed due to this objection ratione temporis, which supports the idea that the ‘as soon as
possible’ requirement is indicative. Providing the application was made before the dead-
line, the Court considers it admissible.
In the Continental Shelf (Libya/​Malta) case, Italy’s application was made only two days
before the time limit for the filing of the counter-​memorials, but the Court held that it
was not out of time.114 In the Pulau Ligitan case, the Philippines submitted their applica-
tion a few days after the closure of the written pleadings. The Court considered it inad-
missible on substantive grounds, but it equally insisted that
[t]‌he time chosen for the filing of the Application . . . can hardly be seen as meeting the requirement
that it be filed “as soon as possible” as contemplated in Article 81, para. 1, of the Rules of Court.
This requirement which, although when taken on its own might be regarded as not sufficiently
specific, is nevertheless essential for an orderly and expeditious progress of the procedure before
the Court. In view of the incidental character of intervention proceedings, it emphasizes the need
to intervene before the principal proceedings have reached too advanced a stage. In one of the re-
cent cases, dealing with another type of incidental proceedings the Court observed that: ‘the sound
administration of justice requires that a request for the indication of provisional measures . . . be
submitted in good time’ . . . . The same applies to an application for permission to intervene, and
indeed even more so, given that an express provision to that effect is included in Article 81, para.
1, of the Rules of Court.115

In the Jurisdictional Immunities of the State case, Greece filed its Application for permis-
sion to intervene one day before the date of the closure of the written pleadings,116 but
the Court made no comment in its order admitting the application concerning the un-
timely filing.
This being said, it is not always easy to anticipate the date of the closure of the written 42
pleadings, since it is not established from the outset of a case, and the number of written

113
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
585, para. 21.
114
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 8, para. 10.
115
Ibid.
116
ICJ Press Release No. 2011/​2 of 17 January 2011.

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 1704 Statute of the ICJ

rounds is generally determined according to the parties’ wishes.117 In the Land, Island and
Maritime Frontier Dispute case, the special agreement between Honduras and El Salvador
bestowing jurisdiction upon the Court allowed for a third round of pleadings, which
meant that the date for the closure of written proceedings remained to be determined
after the filing of the counter-​memorial.118

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43 Similarly, in the Pulau Ligitan case, the Special Agreement provided for the possibility
of one or more round of written pleadings, ‘if the Parties so agree or if the Court decides
so’. The exchange of rejoinders was made on 2 March 2001, whereas the Philippines
filed its application on 13 March 2001. However, it was not until 28 March that the
parties notified the Court that they had agreed that no further rounds of pleadings were
necessary. Thus, the Philippines’ application was filed after the last round of pleadings
had terminated, but on a date when neither the Court nor any third State could know
whether the written proceedings had come to an end. The Court held that the application
complied with the time limits of Article 81, para. 1 of the Rules.119

III. Substantive Conditions
44 The application to intervene must set out how it satisfies each of the substantive require-
ments of Article 81, para. 2 of the Rules, with separate paragraphs addressed to each.
These requirements are:
(a) the interest of a legal nature which the State applying to intervene considers may be
affected by the decision in that case;
(b) the precise object of the intervention;
(c) any basis of jurisdiction which is claimed to exist as between the State applying to
intervene and the parties to the case.
Only requirement (a) is specifically mentioned in Article 62 of the Statute. The Court
clarified that requirement (c) is actually not a requirement for the admissibility of an ap-
plication for permission to intervene, at least not if the third States wishes to intervene as
a non-​party, which is usually the case. Its maintenance in the Rules reflects the continuing
dichotomy of status of the intervener, which the Court has not thus far resolved.
1. Interest of a Legal Nature Which May be Affected by the Decision
45 The first substantive requirement, the existence of an interest of a legal nature which
may be affected by the decision, is also the most difficult to apprehend. The Court’s case
law reveals its marked reluctance to define the concept of ‘interest a legal nature’ and the
threshold at which this interest appears at risk to be affected. It is equally difficult to assess
whether these are two cumulative conditions or rather a single one. On the conceptual
level, the first element is amenable to definition in general terms, according to objective
parameters, while the second is purely circumstantial, a question of fact, depending on
the particular circumstances of a case. The Court treats them, however, together, as if they
were a single condition, combining arguments of fact and law in their analysis.

117
See Miron, ‘Working Methods of the Court’, JIDS 7 (2016), pp. 384–​7.
118
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 98, para. 12.
119
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
586, paras. 24–​6.

miron/chinkin
 Article 62 1705

a) The Interest of a Legal Nature

Three characteristics of the interest-​requirement emerge from the Court’s case law: first, 46
its legal nature; second, the difference with the legal right; third, its concrete and indi-
vidualized character.

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aa) The Legal Nature
It is for the Court to decide whether a State requesting intervention has demonstrated 47
that it has a valid interest of a legal nature120 and to determine the applicable standard of
proof. Although the language of Article 62 is ‘plainly liberal’,121 the jurisprudence around
these requirements shows the Court to have adopted a restrictive interpretation, at least
in classic bilateral disputes such as those involving land or maritime boundaries.122 The
adjective ‘legal’ suggests that this interest is protected under international law. The State
seeking to intervene must thus define its interests by reference to rules of international
law. But the Court only defined this aspect negatively:
Article 62 requires the interest relied upon by the State seeking to intervene to be of a legal nature,
in the sense that this interest has to be the object of a real and concrete claim of that State, based
on law, as opposed to a claim of a purely political, economic or strategic nature.123

bb) The Distinction between the Legal Interest and the Legal Right
The second characteristics of the interest-​requirement under Article 62 concerns its dis- 48
tinction from the close concepts of right and claim. During the drafting of the Statute by
the Advisory Committee of Jurists in 1922, there was discussion as to whether the basis
for requesting intervention should be an ‘interest’ or a ‘right’ that might be affected by the
main dispute.124 The adopted wording was a compromise between these two positions,
which was soon denounced as a ‘monster which defies expression’.125
After using the terms ‘legal rights’ and ‘legal interests’ interchangeably,126 the Court
stated the distinction between them in the intervention cases, at first without any further
analysis:

120
In Judgement No. 273 (Review), Advisory Opinion, ICJ Reports (1982), pp. 325 et seq., the ICJ con-
sidered that a State not a party to proceedings of the UNAT between the Organization and a staff member
could nevertheless have a legal interest in the outcome. The example given was of an error of law as to the in-
terpretation of a provision of the UN Charter to which the State is a party.
121
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Diss. Op. Al-​
Khasawneh, ICJ Reports (2011), pp. 374, 375, para. 5.
122
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
Sep. Op. Cançado Trindade, ICJ Reports (2011), pp. 505, 530, para. 58.
123
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 358–​9, para. 26; ibid., Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 434, para. 37 (emphasis added).
124
Procès-​Verbaux of the Proceedings of the Advisory Committee of Jurists (1920), pp. 593–​4; see Territorial
and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Diss. Op. Al-​Khasawneh, ICJ
Reports (2011), pp. 374, 380, para. 21; ibid., Diss. Op. Cançado Trindade and Yusuf, ICJ Reports (2011),
pp. 402, 406, para. 10.
125
Farag (1927), p. 59.
126
Notably in South West Africa (Ethiopia v. South Africa; Liberia v. South Africa), Second Phase, Judgment,
ICJ Reports (1966), pp. 6, 18–​9, paras. 4–​8, and 20–​2, paras. 10–​5.

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 1706 Statute of the ICJ
In order to be permitted to intervene, a State does not have to show that it has rights which need
to be protected, but merely an interest of a legal nature which may be affected by the decision in
the case.127

In its 2011 judgments in the Territorial and Maritime Dispute case, the Court draw a

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parallel between the legal interests for the purposes of Article 62 and the legal claims or
entitlements of a State.128 It stated that:
The State seeking to intervene as a non-​party therefore does not have to establish that one of its
rights may be affected; it is sufficient for that State to establish that its interest of a legal nature
may be affected. Article 62 requires the interest relied upon by the State seeking to intervene to be of a
legal nature, in the sense that this interest has to be the object of a real and concrete claim of that State,
based on law . . .129

49 The distinction between interests and rights is also discussed in individual opinions.
Judge Abraham noted that an interest ‘is always a notion that is both more flexible and
broader [than that of a right]; . . . one may have an interest to protect without its being
linked, strictly speaking, to a corresponding right, or at least to an established right’.130
Judge Keith asked in his Declaration ‘[i]‌f the claim is based on law and is real and con-
crete, is it not a claim of a right (or a liberty or a power) recognized by the law?’.131 Judge
Keith analysed the earlier requests for intervention to demonstrate the close linkage be-
tween interests of a legal nature and entitlements under international law. The 2011 deci-
sions establish clearly a parallel between the legal interest and the legal entitlement or the
legal claim.132 The three notions do not necessarily coincide: the entitlement is founded
on legal rules, but its precise scope remains to be determined. The legal claim is a sub-
jective proposition of the State, made public. And the interest of a legal nature is possibly
broader and certainly more flexible.133

127
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 129, para. 87. Previously, the ICJ had discussed the difference between
interest and right in Barcelona Traction, Merits, ICJ Reports (1970), pp. 3, 36, para. 46.
128
Charles de Visscher defined the legal interest as entitlement: ‘Invoquer un intérêt juridique c’est se
réclamer à des fins juridiques d’un titre susceptible d’atteindre de telles fins, sans que le bien-​fondé en droit de
ce titre s’en trouve pour autant préjugé.’ (De Visscher, Aspects récents du droit procédural de la Cour internationale
de Justice (1966), p. 63).
129
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 358–​9, para. 26 (emphasis added). See also ibid., Application by Costa Rica for Permission to
Intervene, ICJ Reports (2011), pp. 420, 434, para. 37.
130
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Diss. Op.
Abraham, ICJ Reports (2011), pp. 384, 385, para. 6.
131
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Decl. Keith,
ICJ Reports (2011), pp. 393 et seq., para. 6.
132
Judge Donoghue did not entirely endorse this parallel: ‘The Court today appears to suggest that an
“interest of a legal nature” must be framed as a “claim” of a legal right. The focus on claims may flow from a
body of jurisprudence derived from maritime claims. Nonetheless, although a generalized interest in the con-
tent of international law has been found to be insufficient to comprise an “interest of a legal nature”, I do not
rule out the possibility of a third State demonstrating an “interest of a legal nature” without framing it as a
“claim” of a legal right’ (ibid., Application by Honduras for Permission to Intervene, Diss. Op. Donoghue, ICJ
Reports (2011), pp. 471, 476).
133
The distinction may be important in cases where the third State attempts to intervene in a case and then
seeks adjudication on the subject-​matter of its application to intervention. This is precisely Costa Rica’s pos-
ition in the Caribbean Sea Delimitation. Costa Rica’s claim in the merits of this case (an adjusted equidistance
line: Memorial of Costa Rica, 3 February 2015, pp. 79–​82) goes beyond the line which bordered its area of
interest in its application to intervene (based on a simple equidistance line: Territorial and Maritime Dispute,
Application by Costa Rica for Permission to Intervene, ICJ Reports (2011), pp. 348, 364, paras. 54–​55). The
Court’s Judgment on the merits (Caribbean Sea Delimitation, 2 February 2018) does not even mention Costa

miron/chinkin
 Article 62 1707

The difference between the legal interest, on the one hand, and the legal right, on the 50
other, stands still as long as the parties or the Court do not seek to ascertain the validity
or the soundness of the former.134 This limitation is moreover consistent with the require-
ment that intervention must not seek to introduce a new dispute and that the Court must
refrain from any pronouncement on the legal rights of third States.135

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Interestingly, Honduras’ application illustrates the reverse situation when the Court 51
had already determined the legal rights of the would-​be intervener prior to its applica-
tion for permission to intervene. The Court considered that Honduras could not bring
the evidence of an interest of a legal nature, since the 2007 judgment setting out the
boundary between Nicaragua and Honduras had already established the extent of their
respective legal rights.136 The judgment being dispositive of their legal rights, it was a
fortiori dispositive of its legal interests in the same subject-​matter.137 In the absence of any
right of Honduras in the area to be delimited, the would-​be intervener could not attempt
to bypass the 2007 res judicata by using Article 62 proceedings.138
cc) A Concrete and Individualized Interest
If the legal interest is framed as a claim—​a concrete proposition based on law—​then the 52
determination of general points of law is not enough for the purposes of Article 62. The
interest under Article 62 cannot be a general interest.139 In its order on intervention by
Malta in Continental Shelf (Libya/​Malta) excluded that the interest could rest on the ar-
gument that ‘the resulting judgment might form an important precedent as a subsidiary
means for the ascertainment of the law’.140 And in the Land, Island and Maritime Frontier
Dispute case, the Chamber also stated that it did not consider that ‘an interest of a third
State in the general rules and principles likely to be applied by the decision can justify an
intervention’.141
This is a reasonable approach, for at least two reasons: (i) a contrary position would 53
virtually open the gate of intervention to all States (since they all have an interest to the
determination of the rule of law opposable to them); (ii) intervention under Article 63 of
the Statute is the best vehicle for third states to develop points of law before the Court.
As Bonafé underlines, ‘the protection of general interests of third states in the interpret-
ation of multilateral treaties’142 is preserved by Article 63, whereas ‘the protection afforded
by Article 62 is limited to situations in which the specific interests of a third state may
be affected’.143 Considering however that Article 63 is restricted to the construction of

Rica’s position during the intervention proceedings, which means that the area of interest and the claim do not
necessarily correspond.
134
In the same vein, Palchetti, Max Planck UNYB (2002), p. 144.
135
Cf. infra, MN 77–​83.
136
Territorial and Maritime Dispute between Nicaragua and Honduras in the Caribbean Sea, Judgment, ICJ
Reports (2007), pp. 659 et seq.
137
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 442, para. 64.
138
Ibid., p. 443, paras. 66–​70.
139
See also Queneudec (1995), pp. 419–​20.
140
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 11, para. 16 and p. 17, para. 29.
141
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 124, para. 76.
142
Bonafé, ‘Discretional Intervention (Article 62, Statute of the Court)’, in Latin America and the
International Court of Justice: Contributions to International Law (Almeida/​Sorel, eds., 2017), pp. 98–​108, 99.
143
Ibid.

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 1708 Statute of the ICJ

multilateral conventions—​a vestige of an epoch where international law was considered

to be the exclusive product of the will of the States—​it cannot be invoked in respect to
the determination of rules of customary law. This limitation in Article 63 of the Statute
makes necessary for States to mould their application to fit the requirements of Article
62. As Judge ad hoc Gaja noted:

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[T]‌he only opportunity provided by the Statute and Rules for a State which is not a party to the
proceedings to express its views on an issue of general international law is to intervene under Article
62 of the Statute and address the issue if it is relevant to the intervention.144

54 This appeared to be Greece’s dilemma in the Jurisdictional Immunities of the State case.
Even if in its application Greece stated that it wished to inform the Court of its approach
and practice in relation to the customary rules of immunities only as a matter of back-
ground information,145 in reality most of Greece’s written observations related to ascer-
taining the existence of some rules of customary law.146 Greece changed tack during the
oral hearings, in order to concentrate on how the application of the general rules might
affect its legal obligations.
55 Moreover, the interest should be individualized: the would-​be intervener must seek to
protect its own interest, and not that of one of the parties. In the order on intervention
by Malta in Continental Shelf (Tunisia/​Libya), the Court held that:
The interest of a legal nature invoked by Malta does not relate to any legal interest of its own directly
in issue as between Tunisia and Libya in the present proceedings or as between itself and either one
of those countries.147

56 The requirement may be differently appreciated in case of erga omnes obligations.

The concept of a ‘public interest’ intervention had been indirectly suggested in the
Landwarów–​Kaisiadorys case, where the PCIJ affirmed third State interests in freedom
of transit and communications, noting that ‘nevertheless no third State has considered it
necessary or expedient to intervene’.148 The possibility of intervention in order to protect
a third State interest shared with other members of the international community has not
been directly addressed by the ICJ itself. In the Nicaragua case, Judge Schwebel suggested
that it might be a proper purpose of intervention to raise fundamental questions of inter-
national law on behalf of the international community; that is to assert that all States
would benefit from the Court’s pronouncement on such norms.149
57 In its application to intervene in the Nuclear Tests (Request for Examination) case, the
would-​be interveners pointed out, in similar terms, that most requests for intervention
are in the context of boundary disputes ‘where the third party interest is to a greater or

144
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
Decl. Judge ad hoc Gaja, ICJ Reports (2011), pp. 531 et seq., para. 1.
145
Ibid., Application by the Hellenic Republic for Permission to Intervene, ICJ Reports (2011), pp. 494,
499, para. 18. In the same vein, Kolb, ICJ, p. 228.
146
Greece’s pleadings dealt at length with the existence of a private right to compensation for human rights
violations and the exception to State immunity in case of violations of norms of jus cogens (Ibid., Written
Statement of the Hellenic Republic, 3 August 2011, passim).
147
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 12, para. 19 (emphasis added).
148
Landwarów–​Kaisiadorys, Advisory Opinion, PCIJ, Series A/​B, No. 42, pp. 108, 118.
149
Nicaragua, Provisional Measures, Diss. Op. Schwebel, ICJ Reports (1984), pp. 190 et seq.; ibid.,
Declaration of Intervention of the Republic of El Salvador, Diss. Op. Schwebel, ICJ Reports (1984), pp.
215, 223.

miron/chinkin
 Article 62 1709

lesser extent opposed to those of the parties to the proceedings’.150 In contrast, there is a
community of interest in disputes about obligations owed erga omnes, thereby implying
that there should be a greater willingness on the part of the Court to recognize the ap-
propriateness of the request. The requests to intervene were dismissed along with New
Zealand’s claim in the 1995 Nuclear Tests (Request for Examination) case and the pur-

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ported purpose of intervention, i.e., to uphold obligations owed erga omnes, was not con-
sidered by the Court. Judge Cançado Trindade also developed on the notion of collective
interest and on intervention as a collective guarantee in his opinion on Whaling in the
Antarctic case.151
b) The Risk for the Interest to be Affected
aa) Interpretation of the Term ‘decision’
The Court has generally refrained from establishing general guidelines on how the interest 58
of a legal nature may be affected, but its case law contains some indicia nonetheless. In
Pulau Ligitan, the Court commented on the meaning of ‘decision’ in Article 62:
The word ‘decision’ in the English version of this provision could be read in a narrower or a broader
sense. However, the French version [est pour lui en cause] clearly has a broader meaning. Given that
a broader reading is the one which would be consistent with both language versions and bearing
in mind that this Article of the Statute of the Court was originally drafted in French, the Court
concludes that this is the interpretation to be given to this provision.152

In accordance with the broader meaning that is compatible with both authentic texts,
it determined that the interest of a legal nature could relate not only to the dispositif of
a judgment but may extend to the ‘reasons which constitute the necessary steps to the
dispositif’.153
On the other hand, in Territorial and Maritime Dispute, the Court commented that the 59
English text is more explicit than the French:
The Court observes that, as provided for in the Statute and the Rules of Court, the State seeking to
intervene shall set out its own interest of a legal nature in the main proceedings, and a link between
that interest and the decision that might be taken by the Court at the end of those proceedings. In
the words of the Statute, this is ‘an interest of a legal nature which may be affected by the decision
in the case’ (expressed more explicitly in the English text than in the French ‘un interet d’ordre
juridique . . . pour lui en cause’; see Article 62 of the Statute). 154

The Court also identified the decision as being the judgment on the merits, which would
tend to suggest that intervention under Article 62 would only be possible in relation to
the merits stage:155
150
Request for an Examination of the Situation in Accordance with Paragraph 63 of the Court’s Judgment of 20
December 1974 in the Nuclear Tests (New Zealand v. France) Case, Order of 22 September 1995, ICJ Reports
(1995), pp. 288, 294, para. 19.
151
Whaling in the Antarctic, Declaration of Intervention by New Zealand, Sep. Op. Cançado Trindade, ICJ
Reports (2013), pp. 14, 33–​5, paras. 53–​60.
152
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
596, 597–​8, paras. 47, 55.
153
Ibid., p. 596, para. 47; Territorial and Maritime Dispute, Application by Honduras for Permission to
Intervene, ICJ Reports (2011), pp. 420, 434, para. 38. Cf. also Brown on Art. 59 MN 41 et seq. as well as
Zimmermann/​Thienel on Art. 60 MN 72 and also Damrosch on Art. 56 MN 12–​14, 21.
154
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 433, para. 33 and ibid., Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 358, para. 23.
155
See the discussion supra, MN 21–​25.

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 1710 Statute of the ICJ
It is up to the State concerned to apply to intervene, even though the Court may, in the course of
a particular case, draw the attention of third States to the possible impact that its future judgment
on the merits may have on their interests.156

The Court established that the would-​be intervener must bring evidence of how the

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judgment on the merits may affect its legal interests, either in its dispositive part or in its
reasoning. As a consequence, the interest of a legal nature must be linked to the subject-​
matter of the dispute between the parties or, at least, to the legal grounds on which their
claims are based.157 Beyond these minimal indicia, the Court has not interpreted the
word ‘affected’ and the risk for the interest of a legal nature to be affected can thus only
be appreciated on a case-​by-​case basis. A panorama of the relevant cases shows that any
attempt to draw general guidelines is futile.
bb) A Circumstantial Assessment
60 In the Continental Shelf (Tunisia/​Libya) case, Malta had to word its application in light of
the parties’ compromis, which limited the jurisdiction to indicating ‘principles and rules of
international law which may be applied’. The parties also asked the Court to ‘clarify the
practical method for the application of these principles and rules in this specific situation,
so as to enable the experts of the two countries to delimit those areas without any diffi-
culties’.158 In common with claims in other maritime boundary disputes, Malta’s claimed
legal interest rested upon its location vis-​à-​vis the parties, in that at some point the
boundaries of those States’ continental shelves would come up against its own—​the issue
of ‘overlapping third-​State claims’.159 Since the interest put forward must be concrete, the
Court held that mere preoccupation with the relevant principles of international law that
might be stated in the Court’s judgment is insufficient to support a claim for interven-
tion, for this is a shared interest with other States.160 Further, since Malta had expressly
stated that the purpose of its intervention was not to put its own claims with respect to
Tunisia and Libya, it had in effect denied that it had a legal interest that could be affected
by the decision in the case. This holding concerned a number of judges.161
61 In the follow-​up Continental Shelf (Libya/​Malta) case, Italy expressed its interest in the
litigation between Libya and Malta as a desire to protect its own ‘sovereign rights’ over
its continental shelf. The Court dismissed Italy’s claim, because it considered that to have
granted it would have involved the Court in pronouncing upon Italy’s rights.162 This
rejection presented third States with an apparently insoluble dilemma. If a third State
thinks its sovereign rights may be affected by a decision in pending proceedings, it should
request to intervene. However, if the request involves claiming those sovereign rights, it

156
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 433, para. 33 and ibid., Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 358, para. 23.
157
See also Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports
(1981), pp. 3, 14, para. 23.
158
Art. 1 of the agreement, cited in Continental Shelf (Tunisia/​Libya), Application by Malta for Permission
to Intervene, ICJ Reports (1981), pp. 3, 23, para. 4.
159
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, Judgment, Diss.
Op. Donoghue, ICJ Reports (2011), pp. 471, 477, para. 19.
160
Continental Shelf (Tunisia/​Libya), Application by Malta to Intervene, ICJ Reports (1981), pp. 3, 8–​9,
para. 13.
161
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, Sep. Op. Oda, ICJ
Reports (1981), pp. 23, 31, para. 19; ibid., Sep. Op. Schwebel, ICJ Reports (1981), pp. 35 et seq.
162
Cf. infra, MN 77–​83.

miron/chinkin
 Article 62 1711

may be rejected as going beyond mere intervention and raising a new dispute, different
from the one submitted to the Court by the special agreement. At the same time, if the
third State presents its interests in general terms, its request may be refused as was the
case with Malta. This position appeared insupportable and indeed Judge Ago considered
that the rejection of Italy’s request to intervene sounded the ‘death knell’ for Article 62.163

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The Land, Island and Maritime Frontier Dispute case, the first successful request to 62
intervene under Article 62, suggested this gloomy prognosis to have been premature.
Nicaragua accepted that it had no legal interest in the decision of the Court with respect
to the land frontier between El Salvador and Honduras. It therefore limited its applica-
tion to intervene to the ‘legal situation of the islands and maritime spaces’.164 Nicaragua
stated its legal interest in those areas in general terms. However, in respect of the Gulf, it
asserted:
that both parties, among other questions that affect our interests, are asking the Chamber to define
or clarify the general or overall status of the whole Gulf of Fonseca in which Nicaragua plainly has
rights.165

Since the Central American Court of Justice had in 1917 recognized El Salvador, 63
Honduras, and Nicaragua as ‘co-​owners’ of the Gulf of Fonseca, Nicaragua’s interest was
evident.166 El Salvador and Honduras had different claims with respect to the status of the
waters in the Gulf of Fonseca. El Salvador claimed the waters to be subject to a condo-
minium of the coastal States, while Honduras claimed a ‘community of interest’ between
the riparian States. The Chamber held that it could not prejudge the issue on the merits,
in considering a request to intervene.167 The Chamber held that the claims of both El
Salvador and Honduras affected the legal interests of Nicaragua. El Salvador’s claim of
a condominium was for an objective legal regime of the coastal States which might ‘in
any case . . . be applicable to the Gulf as customary international law’, while the ‘commu-
nity of interests’ claimed by Honduras ‘embraces Nicaragua as one of the three riparian
States’.168 Since the claims of both parties clearly involved Nicaragua, the Chamber up-
held Nicaragua’s request to intervene with respect to the status of the Gulf.
On the other hand, the Chamber found Nicaragua had no legal interest with re- 64
spect to sovereignty over certain islands. As far as the maritime delimitation between El
Salvador and Honduras was concerned, the Chamber considered that the legal interest
of Nicaragua would not be ‘affected’ by such maritime delimitation. It observed that fre-
quently in practice a delimitation between two States involves taking account of the coast
of a third State; but the taking into account of all the coasts and coastal relationships
within the Gulf as a geographical fact for the purpose of effecting an eventual delimita-
tion as between two riparian States in no way signifies that by such an operation itself

163
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, Diss. Op. Ago, ICJ
Reports (1984), pp. 115, 129, para. 22.
164
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 116, para. 58.
165
Ibid., p. 117, para. 60. The specific aspects of Nicaragua’s legal interest are set out ibid., p. 108, para. 37.
166
El Salvador v. Nicaragua, Central American Court of Justice, reprinted in AJIL 11 (1917), pp. 674–​96.
167
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 118, para. 62; repeated in Territorial and Maritime Dispute, Application
by Costa Rica for Permission to Intervene, Judgment, ICJ Reports (2011), pp. 348, 371, para. 85.
168
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 121, para. 72.

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 1712 Statute of the ICJ

the legal interest of a third riparian State of the Gulf, Nicaragua, may be affected.169 In
its rejection of Nicaragua’s request to intervene with respect to the islands and maritime
delimitation the Chamber took the restrictive approach of the Continental Shelf cases be-
tween Tunisia and Libya, as well as Libya and Malta.
65 In the Land and Maritime Boundary case, Nigeria had argued in its preliminary objec-

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tions, for the inadmissibility of the case on the basis of the indispensable third party prin-
ciple. It considered that ‘the question of maritime delimitation necessarily involves the
rights and interests of third States’,170 in particular São Tomé and Principe and Equatorial
Guinea. In response, the Court accepted that the geographical configuration of the Gulf
of Guinea meant that:
it is evident that the prolongation of the maritime boundary between the Parties . . . will eventually
run into maritime zones where the rights and interests of Cameroon and Nigeria will overlap those
of third States.

66 In its application for permission to intervene, Equatorial Guinea claimed that its
legal interests which may be affected were its sovereign rights and jurisdiction ‘up to
the median line between Equatorial Guinea and Nigeria on the one hand, and between
Equatorial Guinea and Cameroon on the other hand’.171 Without developing its rea-
soning, the Court accepted that this established that Equatorial Guinea had an interest
of a legal nature that might be affected by the decision in the case between Cameroon
and Nigeria. 172
67 In the Pulau Ligitan case, the Philippines claimed an interest of a legal nature in the
Court’s reasoning in the case before it, which could affect the outcome of the Philippines’
claims with respect to North Borneo. The Philippines’ interest was in the Court’s findings
and reasoning with respect to various specific treaties that it might rely on in another
dispute between itself and one of the two parties before the Court. The case raised the
interesting question as to whether an interest may be affected, even though it does not
correspond to the subject-​matter of the dispute submitted by the Parties.173 Since the
Court had held that an interest may be affected by the dispositif, as well as by the motives,
it sought to determine whether the basis of title put forward by the Philippines would
be essential to its reasoning. The Philippines was unable to show the Court how the rea-
soning or the interpretation of specific treaties in the case before it might affect a legal
interest of the Philippines.174
68 The case shows that, while not impossible as a matter of principle, it is in practice more
difficult for the would-​be intervener to prove that its interest may be affected by a case,
when they are not related to the subject-​matter submitted to the Court. More generally,
the Court held that:

169
Ibid., p. 124, para. 77.
170
Land and Maritime Boundary, Preliminary Objections, ICJ Reports (1998), pp. 275, 322, para. 112.
171
Ibid., Order of 21 October 1999, ICJ Reports (1999), pp. 1029, 1031, para. 3.
172
Ibid., p. 1034, para. 13.
173
‘[T]‌he Court will at the outset consider whether a third State may intervene under Article 62 of the
Statute . . . when the State seeking to intervene has no interest in the subject-​matter of that dispute as such, but
rather asserts an interest of a legal nature in such findings and reasonings that the Court might make on certain
specific treaties that the State seeking to intervene claims to be in issue in a different dispute between itself and
one of the two Parties to the pending case before the Court.’ (Pulau Ligitan, Application by the Philippines for
Permission to Intervene, ICJ Reports (2001), pp. 575, 595–​6, para. 46).
174
Cf. supra, MN 58–​59.

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 Article 62 1713
The wish of a State to forestall interpretations by the Court that might be inconsistent with re-
sponses it might wish to make, in another claim, to instruments that are not themselves sources of
the title it claims, is simply too remote for purposes of Article 62.175

One may wonder if a contrario the legal right of a third State may be affected in case the

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Court is called to interpret and apply a legal instrument which is also the source of a title
for a third State (with the exception of multilateral, general conventions, like UNCLOS).
In the Territorial and Maritime Dispute case, the Court reverted to its restrictive ap- 69
proach to intervention that had apparently been softened in the cases of Nicaragua and
Equatorial Guinea. In language drawing upon that used in earlier requests for interven-
tion Costa Rica stated its interest of a legal nature to be its ‘interest in the exercise of its
sovereign rights and jurisdiction in the maritime area in the Caribbean Sea to which it
is entitled under international law by virtue of its coast facing on that sea’.176 The Court
accepted that Costa Rica had demonstrated an interest of a legal nature in specified mari-
time areas.177 However, in order to comply with Article 62, the interest of a legal nature
‘is not just any kind’ but must be one that may be affected ‘in its content and scope, by
the Court’s future decision in the main proceedings’.178 It considered that in those pro-
ceedings it could protect third State interests by ending any delimitation line ‘before it
reaches an area in which the interests of a legal nature of third States may be involved’.179
Accordingly Costa Rica had not satisfactorily demonstrated that its (recognized) legal
interest would be affected by the Court’s decision in the main case. As in the case of
Equatorial Guinea, this protective stance by the Court would apply to any third State,
whether seeking to intervene or not, thereby undermining the reason for seeking inter-
vention in boundary cases.180 The treatment by the Court of Costa Rica’s request shows
that the existence of an interest of a legal nature (acknowledged) does not necessarily
mean it will also be affected (the application was rejected on this ground). Thus, para. 2
(a) of Article 81 of the Rules appears to refer to two distinct requirements, even though
the Court has not always treated them as such.181
In the same case, Honduras, on the other hand, primarily requested intervention as 70
a party and, in the alternative, as a non-​party. It framed its object of intervention dif-
ferently in each case. As a State requesting intervention as a party, Honduras sought
determination of the maritime boundary between itself and Nicaragua and Colombia.
If permission to intervene as a party was refused but permission to intervene as a non-​
party granted, Honduras wanted ‘to protect its rights and legal interests and to inform
the Court of the nature of these, so that they are not affected by the future maritime
delimitation between Nicaragua and Colombia’.182 In its judgment, the Court rejected

175
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
603, para. 83.
176
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 364, para. 54.
177
Nicaragua disputed the areas but the Court determined that it did not have to examine the geographical
parameters of the areas in question; ibid., p. 367, para. 65.
178
Ibid., p. 358, para. 26.
179
Ibid., p. 372, para. 89. The Court drew upon its earlier jurisprudence, notably Maritime Delimitation in
the Black Sea, Judgment, ICJ Reports (2009), pp. 61, 100, para. 112.
180
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 372, para. 86.
181
Cf. supra, MN 45.
182
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 429, para. 18.

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 1714 Statute of the ICJ

both of Honduras’ submissions. It emphasized that the elements stipulated by Article 62

and Rule 81 must be satisfied regardless of the requested capacity for intervention.183 It
considered that Honduras’ request related to two issues: whether the Court’s judgment in
2007 had settled the entire maritime boundary between Honduras (a party to the earlier
case) and Nicaragua184 and the effect the Court’s decision in the current case might have

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on Honduras’ rights under the 1986 Maritime Delimitation Treaty between Honduras
and Colombia.185 The Court found that Honduras could not have an interest of a legal
nature in the area to be delimited, at least not vis-​à-​vis Nicaragua,186 and its legal claims
vis-​à-​vis Columbia, based on the 1986 Treaty, could not in any case be affected, since
the Court ‘would not place any reliance’187 on that instrument in the main proceedings.
71 In the Jurisdictional Immunities of the State case, Greece initially referred to an interest
of a general nature regarding State immunities in case of violations of jus cogens,188 then
narrowed its submission to the enforcement of judgments given by Greek courts in
Italy,189 which Germany claimed to be a breach of its jurisdictional immunities by the
Respondent. Without much explanation, the Court determined that it was sufficient
to establish that Greece had an interest of a legal nature in the main proceedings that
it might have to consider the decisions of the Greek courts in making findings in those
proceedings.190
c) Relationship between Articles 62 and 59 of the Statute
72 Besides the absence of definition of the term ‘affected’, the most problematic aspects
stem from the Court’s changing position on the relationship between Articles 62 and
59 of the Statute. It results from a majority of the Court’s relevant decisions that the
interest of a legal nature of a third State cannot be affected as long as it is protected by
the relative effect of the res judicata, a principle enshrined in Article 59 of the Statute. In
its earlier decisions, the Court considered that the existence of overlapping claims in the
area to be delimited was not enough to establish that the interest of a third State might
be affected.191 But in the Land and Maritime Boundary case, the Court reversed this pos-
ition, asserting that ‘in the case of maritime delimitations where the maritime areas of
several States are involved, the protection afforded by Article 59 of the Statute may not
always be sufficient’.192 It then admitted Equatorial Guinea’s intervention, even though,
in its judgment on the merits, it nonetheless protected the interests of all third States

183
Ibid., p. 432, para. 30.
184
Territorial and Maritime Dispute between Nicaragua and Honduras in the Caribbean Sea, Judgment, ICJ
Reports (2007), pp. 659 et seq.
185
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 439, para. 59.
186
Cf. supra, MN 51.
187
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 444, para. 73.
188
Cf. supra, MN 54.
189
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
ICJ Reports (2011), pp. 494, 499, paras. 16–​8.
190
Ibid., pp. 501–​2, para. 25. For a different assessment, ibid., Decl. Judge ad hoc Gaja, p. 531, para. 2.
191
E.g., Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports
(1984), pp. 3, 26, para. 42 (‘the rights claimed by Italy would be safeguarded by Art. 59 of the Statute’). Land,
Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene, Judgment, ICJ
Reports (1990), pp. 92, 124, para. 77 quoted in Territorial and Maritime Dispute, Application by Costa Rica
for Permission to Intervene, ICJ Reports (2011), pp. 348, 371, para. 85. Cf. supra, MN 60–​71.
192
Land and Maritime Boundary, Judgment, ICJ Reports (2002), pp. 303, 421, para. 238.

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 Article 62 1715

potentially affected by determining that ‘the boundary line continues until the point at
which it reaches the area in which the rights of a third State may be affected’.193 A State
that has unsuccessfully sought intervention may be in a better situation in that it has dir-
ectly alerted the Court to its interests, but the Court’s assertion in the Land and Maritime
Boundary case that it could not rule on Cameroon’s claims in a way that might affect

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Equatorial Guinea and São Tomé and Principe’s rights194 entailed the intervening State,
Equatorial Guinea and the non-​intervening State, São Tomé and Principe being accorded
the same consideration.195
By contrast, the 2011 judgments in Territorial and Maritime Dispute mark a return
to the excessively formalistic approach according to which Article 59 provides sufficient
protection of the interests of third States:
[T]‌o succeed with its request, Costa Rica must show that its interest of a legal nature in the mari-
time area bordering the area in dispute between Nicaragua and Colombia needs a protection that is
not provided by the relative effect of decisions of the Court under Article 59 of the Statute.196

A number of judges have expressed scepticism about the effectiveness of Article 59 to 73

protect third States. They stressed the fact that, if Article 59 is seen as providing adequate
protection for third States, Article 62 would be redundant. Judge Jennings, e.g., described
the purpose of Article 59 to be ‘to prevent legal principles accepted by the Court in a
particular case from being binding also upon other States or in other disputes’.197 In a
judgment allocating rights and duties, Article 59 provides a purely technical protection
which is unlikely to be determinative.198 Judge Jennings rejected what he considered to
be ‘enervating bilateralism’ and did not accept that Article 59 could displace Article 62.199
Judge Oda has emphasized that Article 59 may not be accepted as guaranteeing that a
decision of the Court in a case regarding title would not affect a claim by a third State to
the same title.200 Judge Sette-​Camara suggested that Article 59 goes to the doctrine of res
judicata and not that of precedent201 in that it determines the rights and obligations of
the parties inter se and is silent on the subsequent impact of the decision on third States.
Judge Al-​Khasawneh considered Article 59 and Article 62 to be entirely different in their
scope. The former protects a non-​intervening third State from the effects of res judicata,

193
Ibid.
194
Land and Maritime Boundary, Judgment, ICJ Reports (2002), pp. 303, 421, para. 238.
195
Cf. also Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ
Reports (2011), pp. 348, 372, para. 86.
196
Ibid., p. 372, para. 87 (emphasis added).
197
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, Diss. Op. Jennings,
ICJ Reports (1984), pp. 148, 157, para. 27. Judge Jennings was referring to the objective of Art. 59 as defined
by the PCIJ in Certain German Interests, Merits, PCIJ, Series A, No. 7, pp. 3, 19.
198
‘[T]‌he slightest acquaintance with the jurisprudence of this Court shows that Article 59 does by no
manner of means exclude the force of persuasive precedent. So, the idea that Article 59 is protective of third
States’ interests in this sense, at least is illusory’. (Continental Shelf (Libya/​Malta), Application by Italy for
Permission to Intervene, Diss. Op. Jennings, ICJ Reports (1984), pp. 148, 157, para. 27). Cf. also Brown on
Art. 59 MN 50 et seq.
199
‘Quite apart from the dangers, inadequacies and infelicities which would result from using Art. 59
as a vehicle for importing an inappropriate bilateralism or relativism into the judgments of the Court con-
cerning “sovereign rights”, the complete answer to the argument that Italy is sufficiently protected by Art.
59 is simply that Art. 62 is just as much part of the Court’s Statute as is Art. 59.’ (Continental Shelf (Libya/​
Malta), Application by Italy for Permission to Intervene, Diss. Op. Jennings, ICJ Reports (1984), pp. 148,
159, para. 34).
200
Ibid., Diss. Op. Oda, ICJ Reports (1984), pp. 90, 102, para. 27.
201
Ibid., Diss. Op. Sette-​Camara, ICJ Reports (1984), pp. 71 et seq.

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 1716 Statute of the ICJ

while Article 62 gives ‘a would-​be intervener a chance to be heard in order to protect an

interest before the merits’.202 Similarly, Judges Cançado Trindade and Yusuf stated that
reliance on Article 59 deprives States from informing the Court of its interests before the
main decision, stressing that Article 62 explicitly involves third States in legal proceed-
ings, a matter of increased importance in light of the ‘ever-​increasing complexity and

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multilateralization of international relations’.203
74 It remains to be seen whether this restrictive approach of the Court is adopted only for
maritime delimitation cases. In the Jurisdictional Immunities of the State case, the Court
did not even mention Article 59. Besides, one can imagine that Article 59 does not ensure
sufficient protection in other law of the sea cases. This may, for instance, be the case with
the application of Article 121 UNCLOS and the determination of the status of some
maritime features, claimed by the Parties, but also by third States.204

IV. The Object of Intervention

75 Article 81, para. 2 (b) of the Rules of Court introduced another substantive requirement
that a State must specify the precise object of its request to intervene. The Court must
consider ‘the object of the Application and the way in which that object corresponds to
what is contemplated by the Statute’.205 Yet, Article 62 makes no reference to the proper
object of intervention and nor did any of the earlier Rules of Court. This requirement
is all the more difficult to apprehend that, in English, the term ‘object’ has a double
meaning, either material, ‘a thing that is not living’,206 or subjective, ‘a reason for doing
something, or the result you wish to achieve by doing it’.207 In the context of inter-
vention, these two understandings are used alternatively,208 even if the purpose-​oriented
meaning appears predominant.
76 The identification of a proper object for intervention has long been considered
through the prism of the relationship between the intervening State and the parties.
Consequently, the object of intervention has been mainly analysed through the lens
of dispute-​settlement, and became thus intrinsically conditioned by considerations of

202
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Diss. Op. Al-​
Khasawneh, ICJ Reports (2011), pp. 374, 378, para. 14.
203
Ibid., Diss. Op. Cançado Trindade and Yusuf, ICJ Reports (2011), pp. 402, 413, paras. 26–​7.
204
The arbitral tribunal encountered this kind of difficulty in the South China Sea Arbitration, in relation
to a number of features claimed not only by the Parties, but also by Vietnam or Taiwan (South China Sea
Arbitration (Philippines v. China), PCA Case No. 2013-​19, Award of 12 July 2016, paras. 43, 157, 89, 92,
401). See also Wolfrum, supra, fn. 2, p. 220.
205
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 128, para. 85.
206
Cambridge Dictionary Online, <http://​dictionary.cambridge.org>.
207
Ibid.
208
Compare for instance the different formulations retained by the Court in the Territorial and Maritime
Dispute judgments under the heading ‘The Precise Object of the Intervention’. In relation to Costa Rica’s ap-
plication, the Court used the purpose-​oriented understanding:
In the opinion of the Court, the precise object of the request to intervene certainly consists in informing the
Court of the interest of a legal nature which may be affected by its decision in the dispute between Nicaragua
and Colombia, but the request is also aimed at protecting that interest. (Territorial and Maritime Dispute,
Application by Costa Rica for Permission to Intervene, ICJ Reports (2011), pp. 348, 360, para. 33).
By contrast, the Court adopted the material approach in relation to Honduras’ application, the object of the
intervention becoming similar, if not identical, with the interest requirement: ‘the State seeking to intervene is
required by the Statute to demonstrate the existence of a legal interest which may be affected by the decision of
the Court in the main proceedings.’ (Ibid., Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 435, para. 44).

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 Article 62 1717

consent, jurisdictional link and effect of the judgment on the intervener. 209 However,
intervention ‘cannot have been intended to be employed as a substitute for contentious
proceedings’.210 Logically, the Court considers that requests from a third State to adjudge
its own claims or the introduction of a new dispute are objects incompatible with the
functions of intervention. This reflects the incidental nature of intervention, which must

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remain within the bounds of the dispute submitted by the Parties. On the other hand,
even if Article 62 identifies its purpose as the protection of third States’ legal interests, the
information of the Court on relevant factual and legal aspects, as well as the protection of
collective interests are also proper objects.
1. The Improper Object: Intervention Must Not Introduce a New Dispute
Intervention must not introduce a new dispute, for this would be at odds both with its 77
incidental nature,211 with the functions of intervention and possibly with the principle of
consent to jurisdiction. Since intervention must not introduce a new dispute, its ‘precise
object . . . must be connected with the subject of the main dispute’ between the parties to
the main proceedings.212
In the Continental Shelf (Tunisia/​Libya) case, Malta’s expressed purpose of interven- 78
tion was to submit its views on ‘particular geographical and geomorphological factors,
special circumstances or the application of equitable principles’.213 Malta stressed that
its purpose was not to seek any ruling on matters concerning its own continental shelf,
but that it was anxious lest the Court’s decision affect its interests. The Court rejected the
application nonetheless, on grounds that ‘Malta . . . assumes existing rights . . . to areas of
continental shelf opposable to the claims of the two States Parties to the dispute before
the Court’,214 simply because its pleadings related to the area in dispute between Tunisia
and Libya. By the same token, the Court risked prejudging the merits of Malta’s disputes
with the two parties.215
In the Continental Shelf (Libya/​Malta) case, Italy insisted that there was no dispute 79
between itself and the parties It argued nonetheless that it sought ‘to participate in the
proceedings to the full extent necessary to enable it to defend the rights which it claims over
some of the areas claimed by the Parties’.216 Italy formulated the object of its application

209
Cf. notably Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, Sep.
Op. Oda, ICJ Reports (1981), pp. 23 et seq.; ibid., Sep. Op. Schwebel, ICJ Reports (1981), pp. 35 et seq.;
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, Sep. Op. Mbaye, ICJ Reports
(1984), pp. 35 et seq.; ibid., Diss. Op. Oda, ICJ Reports (1984), pp. 90 et seq.
210
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 134, para. 99.
211
‘An incidental proceeding cannot be one which transforms that case into a different case with different
parties.’ (Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 134, para. 98; Territorial and Maritime Dispute, Application by
Honduras for Permission to Intervene, ICJ Reports (2011), pp. 420, 435, para. 44).
212
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 435, para. 44.
213
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports
(1981), pp. 3, 17, para. 29. For a discussion on the purpose of Malta’s request cf. Jessup, ‘Intervention in the
International Court’, AJIL 75 (1981), pp. 903–​9.
214
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 18, para. 31.
215
Ibid.
216
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 21, para. 33 (emphasis put by the Court, when quoting Italy’s Application).

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 1718 Statute of the ICJ

by reference to its legal rights, not interests as required by Article 62.217 Even if the
Court insisted that it was for itself to determine whether the request raised a new dispute
and to isolate the true object of the application,218 this reference to ‘legal rights’ in the
Application and throughout proceedings led it to consider that it would necessarily have
‘to make a finding as to Italy’s rights (to the extent they are opposed to Malta’s and Libya’s

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claims)’.219 The Court concluded that it is not a valid purpose of intervention to allow a
third State to introduce an extraneous dispute, since this would run contrary to the car-
dinal principle of consent to jurisdiction.220
80 In the Land, Island and Maritime Frontier Dispute case, Nicaragua had to avoid the
pitfalls of the Continental Shelf (Tunisia/​Libya) case and the Continental Shelf (Libya/​
Malta) case. It claimed that its purposes for intervention were to protect its legal interests
in the Gulf of Fonseca ‘by all legal means available’.221 El Salvador argued that this object
‘necessarily involves the inclusion in such means of “that of seeking a favourable judicial
pronouncement” on its own claims’.222 The Chamber held that ‘[t]‌he “legal means avail-
able” must be those afforded by the institution of intervention for the protection of a
third State’s legal interests. So understood, that object cannot be regarded as improper.’223
81 The case reinforces the dilemma of intervention noted earlier:224 ‘[o]‌nce a state identi-
fies the existence of specific rights to which it is a claimant, it is faced with the problem
of explaining how it is seeking to protect its interests without becoming a party to the
litigation’.225 The Chamber sought to bypass this dilemma by holding that intervention
must not seek to and cannot result in adjudging claims of the intervener:
the object stated first in Nicaragua’s Application, namely ‘generally to protect the legal rights of
the Republic of Nicaragua in the Gulf of Fonseca and the adjacent maritime areas by all legal
means available’, is not to be interpreted as involving the seeking of a judicial pronouncement on
Nicaragua’s own claims.226

82 It appears that the Chamber was willing to allow some effectiveness to the procedure
of intervention under Article 62. It managed to do so by clarifying that the purpose of
intervention is to protect the entitlements of the third State and not to provide their de-
finitive recognition nor to adjudge them.227
83 The condition for the application to remain within the bounds of the main case must
not be taken for an occasion for a third State to seek to be identified with either of the
parties to the proceedings. The would-​be intervener is an independent participant raising
its own concerns. During the PCIJ period, it was envisaged that ‘[a]‌n intervenor may

217
Cf. supra, MN 48–​51.
218
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 19, para. 29, citing Nuclear Tests (Australia v. France; New Zealand v. France), Judgments, ICJ Reports
(1974), pp. 253, 262, para. 29, and pp. 457, 466, para. 30.
219
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 21, para. 33.
220
Ibid., pp. 22–​4, paras. 34–​7.
221
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 108, para. 38.
222
Ibid., p. 131, para. 91.
223
Ibid., p. 131, para. 92.
224
Cf. supra, MN 61.
225
Greig, Va. JIL (1992), p. 306.
226
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 131, paras. 91–​2.
227
See Palchetti, Max Planck UNYB (2002), pp. 148–​9.

miron/chinkin
 Article 62 1719

make an independent claim, or it may side with one of the previous parties’.228 In the
Wimbledon case, Poland wished to intervene on the side of the four applicant States
against Germany. In the Nuclear Tests cases, Fiji’s interests were aligned with those of
Australia and New Zealand against France. But if a State wishes to present common argu-
ments with one of the parties, without putting forward any specific interest,229 it should

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seek to join the proceedings, or commence its own action, if it can establish jurisdiction.
Otherwise, the status of the intervener, beneficiary of rights and submitted to little obli-
gations, would be too disruptive of the equality between the parties.
2. The Proper Object: Protection of Legal Interests and Information of the Court
On its face, Article 62 has two intertwined functions: protective of the interests of a third 84
State possibly affected and informative of these interests. The would-​be interveners seek
to set out how their application tends to fulfil this double function, considering that the
informative function alone is not sufficient. In the Continental Shelf (Libya/​Malta) case,
Italy argued that allowing it to intervene would assist the Court in establishing an overall
picture of the situation that it would not receive from the parties’ representations alone.
The Court rejected this offer on the grounds that the test for intervention is not whether
it would be useful, or even necessary, for the Court to receive further information, but
whether the criteria of Article 62 are met.230 In the Land, Island and Maritime Frontier
Dispute case, the Chamber found that:
[I]‌t is perfectly proper, and indeed the purpose of intervention, for an intervener to inform the
Chamber of what it regards as its rights or interests, in order to ensure that no legal interest may be
‘affected’ without the intervener being heard.231

In the Land and Maritime Boundary case, Equatorial Guinea relied again on the double 85
functions of Article 62, its purpose being to ‘inform the Court of the nature of the legal
rights and interests of Equatorial Guinea that could be affected by the Court’s deci-
sion’,232 and thus to ‘protect the legal rights of the Republic of Equatorial Guinea . . . by
all legal means available’.233 The Court reiterated the language of the Chamber in the
Land, Island and Maritime Frontier Dispute case in holding this to be a proper purpose of
intervention,234 as well as in Pulau Ligitan case.235
Having in mind Nicaragua’s and Equatorial Guinea’s successful precedents, Costa Rica 86
adopted similar language,236 insisting both on the preventive and informative functions

228
Hudson, PCIJ, p. 371, citing the Procès-​Verbaux of the Proceedings of the Advisory Committee of
Jurists (1920), p. 745.
229
The question is however different in case of erga omnes obligations (cf. supra, MN 56–​57).
230
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 25, para. 40.
231
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 130, para. 90 (emphasis added).
232
Land and Maritime Boundary, Order of 21 October 1999, ICJ Reports (1999), pp. 1029, 1031, para. 3.
233
Ibid., p. 1032, para. 4.
234
Ibid., p. 1034, para. 14.
235
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
606, para. 88. The Court was referring to its judgment in Land and Maritime Boundary, Order of 21 October
1999, ICJ Reports (1999), pp. 1029 et seq., and that of the Chamber in the Land, Island and Maritime Frontier
Dispute case, Application by Nicaragua for Permission to Intervene, Judgment, ICJ Reports (1990), pp. 92
et seq.
236
Territorial and Maritime Dispute, Application by Costa Rica for Permission to intervene, Judgment, ICJ
Reports (2011), pp. 348, 354, para. 12.

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 1720 Statute of the ICJ

of Article 62. The Court expressly endorsed the terminology and seemed to adhere to the
underlying philosophy:
The decision of the Court granting permission to intervene can be understood as a preventive one,
since it is aimed at allowing the intervening State to take part in the main proceedings in order to

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protect an interest of a legal nature which risks being affected in those proceedings.237

Greece too kept its objective straightforward: ‘to inform the Court of the nature of the
legal rights and interests of Greece that could be affected by the Court’s decision in light
of the claims advanced by Germany to the case before the Court’. Referring to its order
with respect to Costa Rica, the Court approved this as a proper object of intervention.238
3. Degree of Specificity of the Application
87 It is not easy to assess the degree of specificity required for an application for permission
to intervene to be admissible: too vague assertions are incompatible with Article 81 para.
2 (b) which refers to the ‘precise object’ of intervention and would also be at odds with
the requirement that its interest must be concrete and specific.239 Too much detail, on the
other hand, may either bring the application close to the introduction of a new dispute
or make intervention itself superfluous.
88 In Land, Island and Maritime Frontier Dispute case, El Salvador asserted that Nicaragua’s
application failed ‘to indicate its position with respect to the fundamental issue in the
case, which is to define the object of the litigation’.240 El Salvador argued that Nicaragua
had not specified what rights it claimed, how they might be affected by the decision in
the case, or the substantive objectives it hoped to achieve.241 The Chamber held that
Nicaragua’s purpose in requesting intervention could have been expressed more precisely,
but that the imprecision did not warrant rejection of the application in limine, as re-
quested by El Salvador.242
At the same time, and quite contradictorily, El Salvador made the argument that the
admissibility proceedings are enough for intervention to fulfil its protective purpose:
If the object of the intervention is to inform the Court of its rights or claims, Nicaragua will have
a full opportunity to do so in the oral proceedings . . . without any need to allow its intervention.
If, on the other hand, the object of its application is to protect its claims by all legal means . . . then
such a purpose will signify the introduction by Nicaragua of additional disputes.243

The Chamber rightly recognized that the consequence of El Salvador’s argument would
be that a request to intervene would almost never succeed ‘if not for one reason then for
the other’.244

237
Ibid., p. 359, para. 27 (emphasis added).
238
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
ICJ Reports (2011), pp. 494, 502, paras. 28–​9.
239
Cf. supra, MN 52–​57.
240
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 111, para. 45.
241
Ibid., p. 129, para. 88.
242
Ibid., pp. 111–​2, para. 45.
243
Ibid., p. 129, para. 88. In a previous case, Judge Nagendra Singh concluded that all the goals of Italy’s
request could have been, and in fact were, achieved by the application to intervene (Continental Shelf (Libya/​
Malta), Application by Italy for Permission to Intervene, Sep. Op. Nagendra Singh, ICJ Reports (1984), pp.
31 et seq).
244
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 130, para. 89.

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 Article 62 1721

In the Territorial and Maritime Dispute case, Costa Rica strived to find the right balance 89
of detail:
Costa Rica argues that it is not its purpose to inform the Court, at this stage, of the full extent of its
interest, which will occur in the second stage of the intervention proceedings, when it will inform

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the Court on the subject in detail and in full. In any event, for Costa Rica, the initial stage cannot
be a substitute for the second stage in providing the Court with information.245

At the admissibility stage, Costa Rica gave sufficient information of the extent of its
interests, based on maritime entitlements, its own claims in the area to be delimited,
even though the Court did not hold this to be a mandatory requirement,246 but refrain
from submitting arguments on the merits of its claims or those of the parties. In rejecting
Costa Rica’s application, the Court seemed to consider it was sufficiently informed, and
no longer required its assistance during the merits phase:
This does not prevent the Court, if it rejects the application for permission to intervene, from
taking note of the information provided to it at this stage of the proceedings.247

In Land, Island and Maritime Frontier Dispute, the Chamber insisted that Nicaragua 90
‘should be permitted to intervene but solely in respect of the Chamber’s consideration
of the legal regime of the maritime spaces within the Gulf of Fonseca’.248 At the merits
stage however, Nicaragua dwelt upon other aspects too. The Chamber noted Honduras’
protests, but declined to trigger any consequences.249 In the Jurisdictional Immunities of
the State case, Greece hesitated as to the proper object of its intervention,250 but the Court
‘limited [it] to the decisions of Greek courts which were declared by Italian courts as en-
forceable in Italy’,251 and Greece followed these instructions during the merits stage.252
These two cases of successful interventions show that, beyond its role as a condition for
the admissibility of the request, the ‘precise object’ requirement plays a role at the merits
stage too. It tends to control upstream that intervention remains within the bounds of the
main case. The scope of intervention is clearly canalized and bounded by the judgment
on admissibility.
4. The Jurisdictional Link
Article 81, para. 2 (c) of the Rules provides that the application ‘shall set out . . . any basis 91
of jurisdiction which is claimed to exist as between the State applying to intervene and
the parties to the case’. The jurisdictional link253 is the reflection of the long-​standing

245
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 362, para. 46.
246
Ibid., p. 367, para. 65 and p. 372, para. 86.
247
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 363, paras. 49–​51; see also ibid., Decl. Gaja, p. 417, para. 4; ibid., Application by Honduras
for Permission to Intervene, Diss. Op. Donoghue, ICJ Reports (2011), pp. 471, 491, para. 57.
248
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 136, para. 103. See also ibid., p. 125, para. 79.
249
Ibid., Judgment, ICJ Reports (1992), pp. 351, 581, para. 371.
250
Cf. supra, MN 71.
251
Jurisdictional Immunities of the State, Judgment, ICJ Reports (2012), pp. 99, 106, para. 10.
252
Ibid., p. 109, paras. 18–​9.
253
The phrase ‘jurisdictional link’ is particular to intervention proceedings. The phrase as such was cornered
in Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981), pp.
3, 20, para. 36 and was adopted by the Chamber in Land, Island and Maritime Frontier Dispute, Application by
Nicaragua for Permission to Intervene, Judgment, ICJ Reports (1990), pp. 92, 133, para. 94.

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hesitations as to how intervention would cope with the fundamental principle of con-
sent. Even if the Court clarified that intervention is a case of statutory jurisdiction,254
the question is not entirely moot. Beyond its historic interest, consent remains a valid
requirement, at least as long as the Court will maintain the possibility for a third State to
intervene as a party.255

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92 The issue of whether an intervening State requires a jurisdictional nexus has been highly
controversial from the outset of the PCIJ. Article 62 is silent on whether a jurisdictional
nexus is required between the would-​be intervener and the parties to the litigation. Nor
is there any cross-​reference between Article 62 and Article 36 on the Court’s jurisdiction
(as there is, e.g., in Article 53).256 In 1922, when Article 62 was drafted, there was still
an assumption that the Court would have compulsory jurisdiction and that the question
of establishing a jurisdictional nexus between an intervening State and the parties would
not arise. An intervening State—​like the parties—​would automatically be subject to the
Court’s jurisdiction. When compulsory jurisdiction was rejected in favour of the juris-
dictional provisions of Article 36 of the PCIJ Statute, the jurisdictional aspect of Article
62 became contentious. The 1922 Committee of Jurists was divided over whether inter-
vention was only available to those States that had accepted the compulsory jurisdiction
of the Court, or whether any State could claim it.257 Judge Anzilotti, for example, argued
that if any State could request intervention: ‘States would hesitate to have recourse to
the Court if they had reason to fear third parties would intervene in their cases’.258 The
President of the Court, Judge Loder, rejected restricting intervention to those States that
had accepted the Court’s jurisdiction as contrary to the Statute259 and would not take a
vote on the proposal. The 1922 Rules of Court were silent on the need for any jurisdic-
tional nexus, as were all the subsequent Rules until 1978.
93 The failure to clarify the question of a jurisdictional link in the Rules of Court allowed
the continuation of two bodies of opinion. One was that Article 62 requires a jurisdic-
tional link between the intervener and the parties, the other that this would be importing
into Article 62 a condition that is not specified within the article.260 This view asserts
that the only relevant conditions are those specified in Article 62 and acceptance of the
Court’s Statute incurs acceptance of the possibility of a State seeking to intervene. That
Article 62 was not abandoned along with compulsory jurisdiction was not due to over-
sight or carelessness. It was a deliberate and calculated decision, as is made clear by its
inclusion as one of the eight points raised for consideration in the Report of 27 October
1927 by Mr Leon Bourgeois to the Council of the League.261 Indeed, John Bassett Moore
hoped that in the absence of compulsory jurisdiction, intervention might ‘prove to be a
means of inducing governments, be they great or small, to come before the Court’ and
thus enhance confidence in the institution.262
254
Cf. supra, MN 25–​27.
255
Cf. infra, MN 120–​127.
256
Cf. von Mangoldt/​Zimmermann on Art. 53 MN 54–​57.
257
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 14, para. 23.
258
Preparation of the Rules of Court of January 30th, 1922, PCIJ, Series D, No. 2, p. 87.
259
Ibid., p. 96.
260
Pulau Ligitan, Application by the Philippines for Permission to Intervene, Sep. Op. Weeramantry, ICJ
Reports (2001), pp. 630, 633, para. 9.
261
Ibid., para. 10.
262
Moore, ‘The Organisation of the Permanent Court of International Justice’, Columb. L. Rev. 22 (1922),
pp. 497–​511, 507.

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 Article 62 1723

The question of whether a jurisdictional link is required between the intervening State 94
and the parties to the case before the Court is connected with that of the status of the
intervener. This has also been controversial. Article 62 of the Statute makes no refer-
ence to intervention as a party or as a non-​party, an apparently deliberate decision.263
Article 59 of the 1922 Rules of Court was silent on both issues, even if the drafters im-

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agined at some point intervention as a joint party.264 The controversy continued through
the Revision of the Rules of Court that commenced in 1933. The discussion was based
on the Registrar’s reports of 14 March 1934 and June 1934, that of the Third Committee,
and the recommendations of the Coordination Commission. Intervention was discussed
at the Court’s 20th meeting on 21 February 1935 and at its 51st meeting on 8 April
1935. Most discussion centred around the related issues of jurisdictional link, the status
of an intervening State as party or non-​party to the proceedings, and that of whether an
intervening State was entitled to appoint a judge ad hoc.265 Despite all the discussions, the
Rules of Court of 1933, 1936, 1946, and 1972 cast no further light on these questions,
In Fiji’s request to intervene in the Nuclear Tests cases, a number of judges had ex- 95
pressed differing views on these matters in separate and dissenting opinions.266 As sum-
marized by Ambassador Quintana:
Fiji’s attempted intervention in the Nuclear Tests cases . . . had so wide a scope that it was considered
by some as a veiled attempt to institute separate proceedings between the third State and France,
rather than a genuine intervention under Article 62. . . . The requests eventually lapsed, given that
the Court found that the applications by Australia and New Zealand became moot, but as a conse-
quence of Fiji’s attitude the Court itself may have felt the need to adopt a stricter approach towards
intervention.267

Consequently, Article 81, para. 2 (c) of the 1978 Rules of Court introduced the 96
‘sweeping and surprising innovation’268 that a State requesting intervention must indicate
any basis for jurisdiction that might exist between itself and the parties to the case. This
provision did not clarify matters for ‘[i]‌t is couched in nebulous language and one does
not know if it is simply a requirement for the information of the Court or a real pre-
requisite, indispensable for the admissibility of intervention in a given case’.269 Far from
definitely establishing a jurisdictional requirement, the insertion of this paragraph in the
Rules had a preventive scope:
This it did in order to ensure that, when the question did arise in a concrete case, it would be
in possession of all the elements which might be necessary for its decision. At the same time the

263
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Diss. Op.
Donoghue, ICJ Reports (2011), pp. 414, 416, para. 9.
264
Cf. supra, MN 35.
265
Elaboration of the Rules of Court of March 11th, 1936, PCIJ, Series D, third addendum to No. 2,
pp. 304–​7.
266
E.g., Nuclear Tests (Australia v. France; New Zealand v. France), Application by Fiji for Permission to
Intervene, Decl. Onyeama, ICJ Reports (1974), pp. 531–​2 and pp. 536–​7; ibid., Decl. Dillard and Waldock,
ICJ Reports (1974), p. 532 and p. 537; ibid., Decl. Jiménez de Aréchaga, ICJ Reports (1974), pp. 533–​4 and
pp. 537–​8; ibid., Decl. by Barwick, ICJ Reports (1974), pp. 533 and 538.
267
Quintana, ICJ Litigation, p. 850 (footnote omitted).
268
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, Diss. Op. Sette-​
Camara, ICJ Reports (1984), pp. 71, 76, para. 32.
269
Ibid.

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 1724 Statute of the ICJ
Court left any question with which it might in future be confronted in regard to intervention to be
decided on the basis of the Statute and in the light of the particular circumstances of each case.270

97 In the Continental Shelf (Libya/​Malta) case, diverse views were again expressed.271
Applying, as usual, the Ockham’s razor’s principle, the present Court and its predecessor

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deliberately avoided for nearly sixty-​two years to pronounce upon the ‘vexed question’272
of a jurisdictional link requirement, considering it wiser to postpone the decision until it
would have no other choice. That was the case in the Land, Island and Maritime Frontier
Dispute case. Once the Chamber had determined that Nicaragua had a legal interest that
might be affected by the decision, and a proper purpose for intervention, it had to de-
termine whether Nicaragua needed to establish a basis of jurisdiction between itself and
the parties. Nicaragua did not claim a jurisdictional link, another ground of objection by
El Salvador. The Court had to weigh third State interests in intervention against those of
the parties in their litigation. It was argued that if a jurisdictional nexus is not required
for intervention, parties could find their proceedings intruded upon by a third State,
which could not commence proceedings against either of them. This could undermine
the requirement of party consent to the Court’s jurisdiction, cause delay and deter States
from using the Court. However, if the Court required a jurisdictional nexus between the
intervening State and the parties, it would reduce still further the likelihood of successful
third State claims.
98 The Chamber determined, for the first time, that a jurisdictional link between
Nicaragua and the parties was not required for intervention as a non-​party. Thus, the
Chamber considered that Article 81, para. 2 (c) merely allowed States to indicate where
there is such a link, and ‘the use of the words “any basis” . . . shows that a valid link of jur-
isdiction is not treated as a sine qua non for intervention’.273 In reaching this position, the
Court based itself on the nature and purposes of intervention as incidental proceedings:
It thus follows also from the juridical nature and from the purposes of intervention that the exist-
ence of a valid link of jurisdiction between the would-​be intervener and the parties is not a require-
ment for the success of the application. On the contrary, the procedure of intervention is to ensure
that a State with possibly affected interests may be permitted to intervene even though there is no
jurisdictional link and it therefore cannot become a party.274

99 A different conclusion applies in case the third States seeks to intervene as a party.
Through this distinction, the Court sought to mitigate the audacity of its finding on the
absence of a jurisdictional link requirement, which it counterbalanced by a finding that
States may become parties to the proceedings, and are thus bound by the judgment, if
consent to the jurisdiction is established:

270
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 16, para. 27.
271
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, Sep. Op. Nagendra
Singh, ICJ Reports (1984), pp. 31 et seq.; ibid., Sep. Op. Mbaye, ICJ Reports (1984), pp. 35 et seq.; ibid.,
Sep. Op. Jiménez de Aréchaga, ICJ Reports (1984), pp. 55 et seq.; ibid., Diss. Op. Sette-​Camara, ICJ Reports
(1984), pp. 71 et seq.; ibid., Diss. Op. Oda, ICJ Reports (1984), pp. 90 et seq.; ibid., Diss. Op. Ago, ICJ
Reports (1984), pp. 115 et seq.; ibid., Diss. Op. Schwebel, ICJ Reports (1984), pp. 131 et seq.; and ibid., Diss.
Op. Jennings, ICJ Reports (1984), pp. 148 et seq.
272
Continental Shelf (Libya/​Malta), Application by Italy for Permission to Intervene, ICJ Reports (1984),
pp. 3, 27–​8, para. 45.
273
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 135, para. 100.
274
Ibid.

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 Article 62 1725
Those States are the ‘parties’ to the proceedings, and are bound by the Court’s eventual decision
because they have agreed to confer jurisdiction on the Court to decide the case, the decision of
the Court having binding force as provided for in Article 59 of the Statute. Normally, there-
fore, no other state may involve itself in the proceedings without the consent of the original
Parties.275

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This distinction between intervention as a party and as a non-​party has been always 100
restated, but never clarified. In the Land and Maritime Boundary case, the full Court
confirmed the Chamber’s approach and held that the juridical nature and the purpose
of the procedure preclude the need for a jurisdictional link between the third State and
the parties:
On the contrary, the procedure of intervention is to ensure that a State with possibly affected
interests may be permitted to intervene even though there is no jurisdictional link and it therefore
cannot become a party.276

In the Jurisdictional Immunities of the State case, the Court simply noted that ‘since Greece
has made clear that it seeks to intervene as a non-​party’ there was no need to establish any
jurisdictional basis in the case.277
The duality of status has had little practical consequences, since there was only one re- 101
quest for intervention as a party. In the Territorial and Maritime Dispute case, Honduras
primarily sought permission to intervene as a party and alternatively, if that request was
not acceded to, as a non-​party.278 In the former case it asserted jurisdiction on the basis
of the American Treaty on Pacific Settlement, Article XXXI,279 to which it is a party as
well as Nicaragua and Colombia. The Court confirmed that ‘the status of intervener as a
party requires . . . the existence of a basis of jurisdiction as between the States concerned,
the validity of which is established by the Court at the time when it permits interven-
tion. However . . . such a basis of jurisdiction is not a condition for intervention as a
non-​party.’280
By not insisting on a jurisdictional link for intervention as a non-​party, the Court has 102
removed at least one hurdle for third States seeking intervention. This approach has clari-
fied the protective and informative nature of the procedure and—​at least theoretically—​
facilitated a request for intervention by a third State in the face of objections by the
parties. On the other hand, the maintenance of the theoretical possibility for a State to
intervene as a party creates confusion and appears to be the only logical reason why para.
2 (c) of Article 81, has not been amended since 1990.

275
Ibid., p. 133, para. 95.
276
Land and Maritime Boundary, Order of 21 October 1999, ICJ Reports (1999), pp. 1029, 1034–​5, para.
15; Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
588–​9, paras. 35–​6.
277
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
ICJ Reports (2011), pp. 494, 502–​3, para. 31.
278
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 431, para. 23.
279
30 April 1948, 30 UNTS 55.
280
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, ICJ Reports
(2011), pp. 420, 432, para. 28.

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 1726 Statute of the ICJ

V. Evidentiary Requirements
1. Evidence and Standard of Proof
103 All the versions of the Rules of Court since 1922 have required an intervener to list the
documentary evidence attached to the application to intervene.281 Article 81, para. 3 of

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the 1978 Rules of Court states: ‘The application shall contain a list of the documents in
support, which documents shall be attached.’
104 Some parties have argued that the application to intervene was not in conformity with
the Rules of Court because of lack of documentary evidence in support of the assertion
of a legal interest.282 The Court has responded that since the State seeking to intervene
bears the burden of proving the conditions required by Article 62 and Rule 81, it is for
that State to decide which documents to submit.283
105 Paragraph 3 of Article 81 has an evidentiary scope, but its incidence upon the admissi-
bility of the request is undeniable.284 Consequently, the Court held that:
The evidence required from the State seeking to intervene cannot be described as restricted or sum-
mary at [the admissibility] stage of the proceedings, because, essentially, the State must establish
the existence of an interest of a legal nature which may be affected by the decision of the Court.285

106 The standard of proof may be difficult to meet because a request for intervention is
necessarily speculative, for neither the third State nor the Court can know at this prelim-
inary stage what the outcome of the main proceedings will be. The wording of Article 62
suggests that the third State should not be put to a high standard of proof. In the Land,
Island and Maritime Frontier Dispute case, Nicaragua asserted that it need show only a
‘provisional standard of proof ’, an assertion rejected by El Salvador and Honduras. The
Chamber held that the State requesting intervention bears the burden of proof286 and
that it must ‘demonstrate convincingly what it asserts’.287 It simultaneously stressed the
subjective wording of Article 62, and required the intervening State to demonstrate to
its satisfaction an interest that according to the Statute it has only to consider ‘“may” be
affected, not that it will or must be affected’.288

281
Art. 59 of the 1922 Rules of Court; Art. 64 of the 1936 and 1946 Rules of Court; Art. 69 of the 1972
Rules of Court.
282
Indonesia made this argument in the Pulau Ligitan case, Application by the Philippines for Permission to
Intervene, ICJ Reports (2001), pp. 575, 587, para. 27; as did Nicaragua in the Territorial and Maritime Dispute
case, Application by Costa Rica for Permission to Intervene, ICJ Reports (2011), pp. 348, 362, para. 45.
283
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 348, 363, para. 48; Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ
Reports (2001), pp. 575, 587, para. 29.
284
In its judgment in Territorial and Maritime Dispute, the Court analysed this requirement under the
heading ‘The Evidence in Support of the Request to Intervene’, while at the same time insisting upon its impact
but it the Court analysed it in relation with the necessary degree of specificity of Costa Rica’s application and
with the substantive requirements (Territorial and Maritime Dispute, Application by Costa Rica for Permission
to Intervene, ICJ Reports (2011), pp. 348, 362–​3, paras. 44–​51.
285
Ibid., p. 363, para. 49.
286
Judge Oda has expressed the opposite view that the burden is on the parties to the main proceedings to
show that the third parties’ interests will not be affected by the decision in that case; Pulau Ligitan, Application
by the Philippines for Permission to Intervene, Diss. Op. Oda, ICJ Reports (2001), pp. 609, 618, para. 14.
287
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene
Judgment, ICJ Reports (1990), pp. 92, 117, para. 61.
288
Ibid.

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 Article 62 1727

2. Access to Written Pleadings

The chances for a State to meet this accommodating standard of proof are also dependent 107
on its knowledge of the ins and outs of the main case. From the outset, the question of the
extent to which the Court’s records should be open to inspection or kept secret was hotly

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debated, especially in the context of intervention.289 There are opposing tensions between
the principle of intervention and the principle of confidentiality.290 A government cannot
make an informed decision whether to request intervention unless it knows the basis
of the parties’ case. However, the parties to legal proceedings may seek to maintain the
privacy of their arguments and documentation, for as long as is compatible with public
proceedings before the Court.
The first Rules of Court favoured access to the parties’ documentation. Article 38 of 108
the 1922 Rules of Court stated:
The Court or the President, if the Court is not sitting, may, after hearing the parties, order the
Registrar to hold the cases and counter-​cases of each suit at the disposal of the government of any
State which is entitled to appear before the Court.291

This Rule privileged third States over the parties. Its object was described as being to assist
a State in determining whether it has a legal interest in the proceedings within the terms
of Article 62 and to assist a State wishing to intervene in framing its request.292
Article 44, para. 2 of the 1936 Rules of Court allowed the Court (or the President if 109
the Court is not sitting), ‘after obtaining the views of the parties’, to decide to allow the
Registrar to hold the documents of the written proceedings in a case at the disposal of
the government of any member of the League of Nations, or any State entitled to appear
before the Court. Article 44, para. 3 then stated:
The Court . . . may, with the consent of the parties, authorise the documents of the written pro-
ceedings in regard to a particular case to be made accessible to the public before the termination
of the case.293

This Rule ensured that the parties were able to put their views about third State access to
their written proceedings and created no special procedure for a State desiring to inter-
vene. Article 44, para. 2 was amended in the 1945 Rules of Court to spell out that the
‘written proceedings’ of a case comprise the ‘pleadings and annexed documents’ and to
make it applicable to members of the United Nations and States entitled to appear before
the ICJ. It was renumbered as Article 48 in the 1972 Rules of Court.

289
Moore, supra, fn. 262, p. 507.
290
Judge Weeramantry identified the opposing imperatives in the following terms:
There is a tension here between the principle of intervention and the principle of confidentiality, for the latter may in
certain cases shut out a legitimate intervention by denying the intending intervener the information necessary for it to
formulate its intervention. The discretion of the Court must therefore be very carefully exercised, especially when the lack
of knowledge of the parties’ pleadings is offered as an excuse for what might be a belated intervention. An intervener’s
actual pleadings could in certain cases be heavily dependent upon a knowledge of the pleadings of the parties. The mere
publication of the special agreement would not give the intervenient the full information it might require.
(Pulau Ligitan, Application by the Philippines for Permission to Intervene, Diss. Op. Weeramantry, ICJ
Reports (2001), pp. 630, 650–​1, para. 44).
291
Rules of Court, PCIJ, Series D, No. 2, p. 569.
292
Fachiri, The Permanent Court of International Justice, its Constitution, Procedure and Work (1925), p. 104.
293
PCIJ, Series D, third addendum to No. 2, pp. 994, 1009.

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 1728 Statute of the ICJ

110 Without being specific to intervention, Article 53 of the 1978 Rules of Court allows a
third State to seek access to the parties’ pleadings:
The Court, or the President if the Court is not sitting, may at any time decide, after ascertaining the
views of the parties that copies of the pleadings and documents annexed shall be made available to

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a State entitled to appear before it which has asked to be furnished with such copies.

111 Article 53 of the Rules of Court reiterates that the Court must ascertain the views of
the parties before deciding whether to allow third States access to the written documents
of the case. The article does not state that the parties’ views are determinative. In fact, it
appears that they are. No party objected to the release of pleadings in the Nuclear Tests
cases and Fiji received them (along with various other States that did not seek interven-
tion). Malta’s, Italy’s, and the Philippines’ requests for pleadings were rejected after the
Court had ascertained that at least one of the parties objected. Nicaragua, Equatorial
Guinea, Costa Rica, and Honduras received the pleadings of the parties in their respective
cases before filing their requests to intervene.294
112 Finally, Article 85, para. 1 of the Rules confirms that a state seeking to intervene does
not have a right to access the pleadings. It provides indeed that a State that has had its
request to intervene accepted has access to the pleadings in the case. This makes it clear a
contrario that until that point, an intervening State has no greater rights than any other
State under Article 53 of the Rules.
113 Lack of access to the parties’ pleadings makes it difficult for a State requesting interven-
tion to frame its application. Malta argued that at least one reason for its lack of precision
in specifying its purpose for intervention was the refusal to grant it access to the parties’
pleadings. Without the pleadings, it could only speculate on the arguments that might
have been submitted by the parties. The Court did not answer this complaint. It was a
point of concern in at least some of the separate opinions that Libya and Tunisia had not
formulated their claims with precision. Judges Oda and Schwebel thought it important
that more precision should not be asked of a third State than of the parties, especially
where the third State is handicapped by its ignorance of the exact scope of the claims.295
114 In the Pulau Ligitan case, the Philippines argued that it suffered a handicap in
identifying its interest through not having access to the parties’ pleadings. Without them,
it could not be sure which treaties were to be relied upon by the parties.296 The Court
responded that there is nothing in the Rules or its practice that makes ‘an inextricable
link’ between seeking access to pleadings and an application to intervene or ‘that the re-
quirement of the timeliness of the Application for permission to intervene may be made
conditional on whether or not the State seeking to intervene is granted access to the

294
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene
Judgment, ICJ Reports (1990), pp. 92, 98, para. 13; Land and Maritime Boundary, Order of 21 October
1999, ICJ Reports (1999), pp. 1029, 1035, para. 17; Territorial and Maritime Dispute, Application by Costa
Rica for Permission to Intervene, ICJ Reports (2011), pp. 348, 354, para. 10; ibid., Application by Honduras
for Permission to Intervene, ICJ Reports (2011), pp. 420, 426, para. 6.
295
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, Sep. Op. Oda, ICJ
Reports (1981), pp. 23 et seq.; ibid., Sep. Op. Schwebel, pp. 35 et seq.
296
Pulau Ligitan, Application by the Philippines for Permission to Intervene, ICJ Reports (2001), pp. 575,
590, para. 39. Judge Oda said that the ‘whole procedure’ (including that the Philippines had had no access
to the pleadings and that Malaysia referred to its pleadings in its written observations and the oral hearings)
struck him as ‘being rather unfair to the intervening State’; ibid., Diss. Op. Oda, ICJ Reports (2001), pp. 609,
619–​20, para. 16.

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 Article 62 1729

pleadings’.297 A State seeking to intervene that has had access to the pleadings is better
able to comply with the requirements of Article 81 of the Rules.

F. Procedures for Consideration of a Request to Intervene

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The procedures for consideration of a request to intervene are identical for the two forms 115
of intervention (Articles 62 and 63) and the Rules of the Court deal with them in the
same provisions (Articles 83 and 84). The Rules have been refined since 1922.
Article 59 of the 1922 Rules of Court stated that:
Such application shall be immediately communicated to the Parties, who shall send to the Registrar
any observations which they may desire to make within a period to be fixed by the Court, or by the
President, should the Court not be sitting.298

In 1926, these procedures were amplified to allow for oral proceedings. A new paragraph
was added to Article 59 of the Rules, which stated:
Such observations shall be communicated to the State desiring to intervene and to all parties. The
intervener and the original parties may comment thereon in Court; for this purpose the matter
shall be placed on the agenda for a hearing . . . The Court will give its decision on the application
in the form of a judgment.
If the application is not contested, the President, if the Court is not sitting, may, subject to any
subsequent decision of the Court as regards the admissibility of the application, fix, at the request
of the State by which the application is made, time limits within which such State is authorised
to file a case on the merits and within which the other parties may file their counter-​cases. These
time limits, however, may not extend beyond the beginning of the session in the course of which
the case shall be heard.299

These provisions were not amended in 1931. In 1936, Article 59 of the Rules was 116
renumbered as Article 64, with some rewording and breaking up of the provisions into
numbered sub-​paragraphs. Article 64, para. 3 of the 1936 Rules of Court essentially
reiterated the position of Article 59 of the 1922 Rules. It required the application to
be communicated to the parties, who had to send their observations in writing to the
Registrar within time limits specified by the Court, or the President if the Court is not sit-
ting. Article 64, para. 4 required that the application be placed on an agenda for hearing.
The article clarified that ‘if the parties have not, in their written observations opposed the
application to intervene, the Court may decide there shall be no oral argument’. Article
64, para. 5 reiterated that ‘the Court will give its decision on the application in the form
of a judgment’.300

297
Ibid., ICJ Reports (2001), pp. 575, 585, para. 22.
298
Rules of Court, PCIJ, Series D, No. 2, p. 573.
299
Revised Rules of Court, 1926, PCIJ, Series D, No. 1, 1st edn., pp. 33, 57.
300
PCIJ, Series D, third addendum to No. 2, p. 1016. As explained in the study by the Registry of the
ICJ, ‘[d]‌uring the travaux preparatoires of the 1926 revision of the Rules of Court, the Registrar proposed
that, in order to take into account the procedure adopted in connection with Poland’s intervention in the S.S.
‘Wimbledon’ case, Article 59 of the Rules should be amended by adding the following sentence: “The Court
will give its decision on the application in the form of a judgment”, and this proposal was adopted. It was in-
corporated into Article 59 of the 1931 Rules of Court and retained in the 1936 (Art. 64), 1946 (Art. 64) and
1972 (Art. 69) revisions.’ (ICJ Yearbook (2014-​2015), p. 97).

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 1730 Statute of the ICJ

117 Article 64 of the 1945 Rules of Court largely reiterated the same procedures, apart
from a new sub-​para. 4, which required the Registrar to transmit copies of the appli-
cation to intervene to members of the United Nations and to other States entitled to
appear before the Court. This new provision required the renumbering of Article 64,
paras. 4 and 5 of the 1936 Rules of Court as Article 64, paras. 5 and 6 of the 1945

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Rules of Court.
118 The 1978 Rules of Court are more detailed with respect to the procedures to be fol-
lowed when a State has made a request to intervene. They are spelled out in Articles 83
and 84.
Article 83
(1) Certified copies of the application for permission to intervene under Article 62 of the
Statute . . . shall be communicated forthwith to the parties to the case, which shall be invited
to furnish their written observations within a time-​limit to be fixed by the Court or by the
President if the Court is not sitting. (2) The Registrar shall also transmit copies to:
(a) the Secretary-​General of the United Nations;
(b) the Members of the United Nations;
(c) other States entitled to appear before the Court;
(d) any other States which have been notified under Article 63 of the Statute.
Article 84
(1) The Court shall decide whether an application for permission to intervene under Article 62 of
the Statute should be granted . . . as a matter of priority unless in view of the circumstances of
the case the Court shall otherwise determine.
(2) If, within the time-​limit fixed under Article 83 of these Rules, an objection is filed to an appli-
cation for permission to intervene, or to the admissibility of a declaration of intervention, the
Court shall hear the State seeking to intervene and the parties before deciding.

The former requirement that the Court give its decision in the form of a judgment was
deleted in the 1978 Rules of Court,301 giving the Court discretion in the form of its deter-
mination. In practice, the Court decides by a judgment, when one of the parties objected
and hearings were organized, and by an order when no such objection was raised.302
119 Objections by either or both of the parties to the application to intervene in their
written or oral observations are given full consideration but are not determinative of the
outcome. Article 62, para. 2 specifies that it is for the Court to decide upon a request to
intervene, which is in accordance with for the principle of statutory jurisdiction303 and
the ‘sound administration of justice’.304 Even if an objection from either party is not de-
terminative, Article 84, para. 2 of the Rules requires the Court to hold a hearing in that
circumstance. The hearing is sometimes necessary to set out clearly the parties’ position in
relation to intervention. It may be unclear whether a party is in fact objecting or whether
it is just putting forward its views. In the Land and Maritime Boundary case, Nigeria’s
written response stated that whether or not the request to intervene is accepted ‘it will in
Nigeria’s view make no difference to the legal position of Nigeria’. Equatorial Guinea read
this as making no objection to its request, but Nigeria argued that Cameroon had mis-
represented Equatorial Guinea’s position with respect to whether the latter was seeking

301
ICJ Yearbook (2014–​2015), p. 97
302
Ibid., p. 99.
303
Cf. supra, MN 25–​27.
304
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, Judgment, ICJ
Reports (2011), pp. 348, 358, para. 25.

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 Article 62 1731

intervention as a party or as a non-​party. The Court found that neither Cameroon nor
Nigeria objected to the request to intervene as a non-​party intervener and no oral pro-
ceedings were held to consider Equatorial Guinea’s (successful) request to intervene.305
Quite often, the parties’ express their objection by contesting that the conditions for 120
admissibility are met, which necessitates substantial developments. In the Territorial and

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Maritime Dispute case, Colombia did not object to the request to intervene by either
Costa Rica or Honduras. In contrast, Nicaragua considered that neither Costa Rica’s
nor Honduras’ request satisfied the requirements of the Statute and Rules of Court.306
The Court interpreted Nicaragua’s response as an objection to the requests to intervene
and oral hearings were held in consecutive weeks in October 2010. In the Jurisdictional
Immunities of the State case, Germany asserted that it did not ‘formally’ object to Greece’s
application for permission to intervene. It nevertheless drew the Court’s attention to ‘cer-
tain considerations’ which it considered indicated that Greece’s request did not comply
with the requirements of Article 62.307 The Court determined not to hold oral hearings
to consider the request but decided that Greece should be given an opportunity to com-
ment on the Parties’ observations, and that they in turn should be able to submit further
written observations.308

G. The Status of the Intervener

I. The Distinction between Intervention as a Party and Intervention
as a Non-​party
The status of an intervening State as a party or non-​party309 to the proceedings has been 121
another point of uncertainty since 1922. It is closely connected to the appreciation of the
relationship between the third State and the parties and to the question of the jurisdic-
tional link.310 In the Advisory Committee’s introduction of the procedure of intervention
in 1922, three positions were identified:
a [third] party may wish to take sides with the plaintiff or the defendant; a [third] party may claim
certain exclusive rights; or a [third] party may request that one of the two requesting States should
withdraw on the ground that it is not the real dominus of the right which it claims. In this latter
case intervention tends to become exclusion, but as a rule a State is content to take joint action with
one of the parties: should this be allowed?311

The Advisory Committee of Jurists answered this question in the affirmative, provided 122
the conditions of what became Article 62 were met. However, the first draft of the 1922

305
Land and Maritime Boundary, Order of 21 October 1999, ICJ Reports (1999), pp. 1029, 1034, para. 11.
306
Territorial and Maritime Dispute, Application by Costa Rica for Permission to Intervene, ICJ Reports
(2011), pp. 354–​5, para. 13; ibid., Application by Honduras for Permission to Intervene, ICJ Reports (2011),
pp. 420, 427, para. 13.
307
Jurisdictional Immunities of the State, Application by the Hellenic Republic for Permission to Intervene,
ICJ Reports (2011), pp. 494, 496, para. 5. Italy did not object to Greece’s application.
308
Ibid., p. 496, para. 6.
309
The concept of a non-​party intervener has been variously described as a ‘participant’, or a ‘quasi-​party’.
Elias rejected the concept of a non-​party intervener, calling it ‘ludicrous to accept the existence of such an en-
igma’; Elias (1983), p. 95.
310
Cf. supra, MN 77.
311
Report of Mr de Lapradelle, Chairman of the Drafting Committee, Procès-​Verbaux of the Proceedings
of the Advisory Committee of Jurists (1920), p. 745.

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 1732 Statute of the ICJ

Rules of Court, where Article 48 stated that the intervener ‘shall take part in the proceed-
ings as a joint party’312 was rejected and the adopted Article 59 of the Rules was silent on
the point. Nor did the subsequent revisions of the Rules of Court clarify either the status
of a State intervening under Article 62, or the rights and obligations of an intervening
State. But it appears from the discussions on the various modifications and amendments

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of the Rules that the PCIJ judges shared the idea that the intervener could be a party to
the case, in its own right or in support of one of the original parties.313
123 Neither the PCIJ nor the ICJ had to decide on these points until Nicaragua’s request to
intervene was accepted in the Land, Island and Maritime Frontier Dispute case.314 Instead
of making a definitive choice on the status of the intervener, the Chamber consecrated
the two possibilities. Thus in case law, the distinction between intervention as a party and
intervention as a non-​party appeared:
[A]‌State which is allowed to intervene in a case, does not, by reason only of being an intervener,
become also a party to the case. It is true, conversely, that, provided that there be the necessary
consent by the parties to the case, the intervener is not prevented by reason of that status from itself
becoming a party to the case.315

Paragraph 99 of the judgement is all but clear. In the first sentence, it seems to oppose
intervener and party, but the second sentence advances the opposing view, according to
which the intervener may become a party, with the parties’ consent. The Chamber added
that such an intervener ‘may ask for rights of its own to be recognized by the Court in
its future decision, which would be binding for that State in respect of those aspects for
which intervention was granted’.316 Thus, according to the Chamber, three characteristics
distinguish intervention as a party from the normal form of intervention: first, the parties’
consent; second, the possibility for the third State to ask the Court to adjudge its claims;
and third, the binding effect on the intervener of that part of the judgment on the merits
which answers to its claims. Each one of them seems to run contrary to the essential char-
acteristics of intervention.
124 The reintroduction of the parties’ consent as a condition of admissibility of interven-
tion runs contrary to the principle of statutory jurisdiction and the firm consequence that
intervention needs not a jurisdictional link.317 Moreover, intervention as a party seems
to be at the free choice of the third State, who must specify in the application whether it
intends to intervene as a party or as a non-​party. Still this is precisely the hypothesis which
the Chamber of the Court sought to neutralize in Land, Island and Maritime Frontier
Dispute case. In its Application, Nicaragua declared that ‘intends to submit itself to the

312
Cf. supra, MN 35–​36.
313
Elaboration of the Rules of Court of March 11th, 1936, PCIJ, Series D, fourth addendum to No. 2,
1943, pp. 268–​70.
314
See the summary of views by Judge Oda (Pulau Ligitan, Application by the Philippines for Permission to
Intervene, Diss. Op. Oda, ICJ Reports (2001), pp. 609 et seq.).
315
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 134–​5, para. 99.
316
Ibid., p. 134, para. 99; Pulau Ligitan, Application by the Philippines for Permission to Intervene,
ICJ Reports (2001), pp. 575, 588, para. 35; Territorial and Maritime Dispute, Application by Honduras for
Permission to Intervene, ICJ Reports (2011), pp. 420, 432, para. 28; ibid., Application by Costa-​Rica for
Permission to Intervene, ICJ Reports (2011), pp. 348, 361, para. 39.
317
Cf. supra, MN 91–​102.

miron/chinkin
 Article 62 1733

binding effect of the decision to be given’. The Chamber opposed to this statement the
following reasoning:
the force of res judicata does not operate in one direction only: if an intervener becomes a party, and is
thus bound by the judgment, it becomes entitled equally to assert the binding force of the judgment

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against the other parties. A non-​party to a case before the Court, whether or not admitted to intervene,
cannot by its own unilateral act place itself in the position of a party, and claim to be entitled to rely on
the judgment against the original parties.318

The possibility given to the third State to put forward its own claims comes at odds with 125
the limitations put on the object of intervention, which must not aim at introducing a new
dispute or putting forward the third State’s claims.319 Finally, recalling the binding effect of
the judgment on the intervener as a party is tautological, since Article 59 of the Statute ap-
plies to all parties. The Chamber seemed to interpret this principle a contrario and reached
the unexpected conclusion that the judgment on the merits could not have any binding
force towards the intervener as a non-​party: ‘the right to be heard . . . does not carry with it
the obligation of being bound by the decision’.320 Thus, the Chamber confined the binding
effect to the res judicata hypothesis, and considered that Article 59 of the Statute proscribes
any such effect towards a non-​party:
The terms on which intervention was granted, as stated in paragraph 102 of the 1990 Judgment, were
that Nicaragua would not, as intervening State, become party to the proceedings. The binding force of
the present Judgment for the Parties, as contemplated by Article 59 of the Statute of the Court, does
not therefore extend also to Nicaragua as intervener.321

This conclusion was criticized by two out of the five members of the Chamber.322 More 126
generally, the view has been expressed that a third State cannot be allowed the benefit of
intervention without some corresponding commitment, a matter of some concern to the
Court in the Continental Shelf (Tunisia/​Libya) case.323 Finally, this conclusion is at odds with
Article 63 of the Statute, under which the intervener is partially bound by the Court’s judg-
ment, without becoming a party to the proceedings.324
In reality, the Chamber’s argumentation tends more to establish a simplified form for 127
the introduction of a new case, between the parties and the third State, which would
allow the latter to make its own claims. Despite the Chamber’s denegation,325 interven-
tion as a party comes close to an alternative to the joining of cases, provided that the
subject-​matter of the dispute remains essentially the same and that the parties’ consent is

318
Land, Island and Maritime Frontier Dispute, Judgment, ICJ Reports (1992), pp. 351, 610, para. 424.
319
Cf. supra, MN 77–​83.
320
Land, Island and Maritime Frontier Dispute, Judgment, ICJ Reports (1992), pp. 351, 609–​ 10,
paras. 421–​4.
321
Ibid., p. 609, para. 421 and p. 610, para. 424.
322
Land, Island and Maritime Frontier Dispute, Judgment, Decl. Oda, ICJ Reports (1992), pp. 619–​20
and Sep. Op. Torres-​Bernárdez, ibid., pp. 629, 730–​1, para. 208. As summed up by Quintana, ‘Judge Oda
appended a declaration stating that in his view Nicaragua would certainly be bound by those parts of the
judgment concerning the matters on which it was admitted to intervene and judge ad hoc Torres Bernárdez,
appended a separate opinion in which he contended that there cannot be rights without correlative obligations,
establishing a parallel to the legal consequences of intervention under Article 63.’ (Quintana, ICJ Litigation,
pp. 899–​900).
323
Cf. Brown on Art. 59 MN 58–​67.
324
Cf. Miron/​Chinkin on Art. 63 MN 62–​67.
325
‘Intervention under Article 62 of the Statute is for the purpose of protecting a State’s “interest of a legal
nature” that might be affected by a decision in an existing case already established between other States, namely

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 1734 Statute of the ICJ

secured. If this understanding is correct, then the status of the intervener as a party has
hardly any distinct meaning. As Judge Abraham put it:
In reality, it follows from that Judgment and from the Judgment on the merits delivered by the
same Chamber in the same case . . . that a third State which is allowed to intervene as a party does

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not acquire the status of intervener on receiving that authorization, but purely and simply that of
a party. From that moment, the proceedings are no longer between two parties, but between three,
and there is no intervener. In short, the third State uses the application for permission to inter-
vene as a way to join the proceedings, not as an intervener—​which is the usual object of such an
application—​but as a party.326

128 This view is nonetheless minority and the Court has maintained the duality of status.327
Honduras’ unique attempt to intervene in the Territorial and Maritime Dispute case being
rejected on account of the lack of a legal interest,328 the Court did not further clarify the
scope of this distinction.

II. The Procedural Rights of the Intervener

129 The procedural consequences of a successful request to intervene were first specified in
Article 65 of the 1936 Rules of Court. The Rules were minimalist and dealt only with the
filing of memorials and counter-​memorials. Article 65 stated that ‘if the party intervening
expresses a desire to file a memorial on the merits’, it may do so within time limits fixed
by the Court and the parties may file counter-​memorials also within fixed time limits.
Article 65, para. 2 of the 1936 Rules repeated a provision introduced in Article 59 of the
1926 Rules of Court that provided for a particular situation where the Court has not
decided upon a request to intervene, and the parties have not objected. In such a case
the President may, if the Court is not sitting and ‘without prejudice to the decision of
the Court on the question of whether the application should be granted’, and determine
time limits for the intervening State to file a memorial on the merits and for the parties to
respond.329 Article 65 of the 1946 Rules of Court repeated Article 65 of the 1936 Rules
of Court.
130 Article 85 of the 1978 Rules of Court is more detailed about the consequences of inter-
vention but make no reference to the effect of the judgment on the intervener. Article
85 states:
(1) If an application for permission to intervene under Article 62 of the Statute is granted,
the intervening State shall be supplied with copies of the pleadings and documents

the parties to the case. It is not intended to enable a third State to tack on a new case, to become a new party,
and so have its own claims adjudicated by the Court. A case with a new party, and new issues to be decided,
would be a new case. . . . As the Court observed in 1984, ‘There is nothing in Article 62 to suggest that it was in-
tended as an alternative means of bringing an additional dispute as a case before the Court—​a matter dealt with
in Article 40 of the Statute—​or as a method of asserting the individual rights of a State not a party to the case.’
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene, Judgment,
ICJ Reports (1990), pp. 92, 132–​3, para. 97, quoting Continental Shelf (Libya/​Malta), Application by Italy for
Permission to Intervene, ICJ Reports (1984), pp. 3, 23, para. 37.
326
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, Diss. Op.
Abraham, ICJ Reports (2011), pp. 447, 452, para. 18.
327
Cf. supra, MN 91–​102.
328
Cf. supra, MN 51.
329
Ibid., and already Art. 59 of the Revised Rules of Court, supra, fn. 299.

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 Article 62 1735

annexed and shall be entitled to submit a written statement within a time-​limit to

be fixed by the Court. A further time-​limit shall be fixed within which the parties
may, if they so desire, furnish their written observations on that statement prior to
the oral proceedings. If the Court is not sitting, these time-​limits shall be fixed by the
President.

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(2) The time-​limits fixed according to the preceding paragraph shall, so far as possible,
coincide with those already fixed for the pleadings in the case.
(3) The intervening State shall be entitled, in the course of the oral proceedings, to
submit its observations with respect to the subject-​matter of the intervention.
In the Land, Island and Maritime Frontier Dispute case, the Chamber, mindful of the 131
fact that this was the first successful claim under Article 62, discussed the procedural
rights of an intervening State. It emphasized that the interveners’ procedural rights do
not correspond with those of the parties.330 Therefore ‘the intervening State . . . does not
acquire the rights, or become subject to the obligations, which attach to the status of
a party’.331 Interestingly, at this stage of this reasoning, the Chamber did not make the
distinction between intervention as a party and intervention as a non-​party, and this
confirms the hypothesis according to which the intervener as a party has the status of a
party.332
Any intervener has the right to be heard, through submission of a written state- 132
ment and participation in the hearings. The intervening State must comply with the
time limits set by the Court. Article 85, para. 3 of the Rules allows the intervener to
be heard by the Court or Chamber only on the subject of the intervention, not on
the case as a whole. This is the logical consequence of the requirement according to
which the application for permission to intervene shall set out the precise object of
intervention.333
Other consequences of intervention are not spelled out in Article 85 of the Rules. 133
The composition of the Court to determine claims of intervention has been the subject
of argument. One issue is whether an intervening State can appoint a judge ad hoc.334
In 1922, the PCIJ rejected a proposal to provide intervening States with this right.335
Successive Rules of Court have remained silent on this point.336 In the Wimbledon case,
Poland stated that it was renouncing its right to appoint a judge ad hoc, because it did not
consider it necessary.337 The question was settled in the negative in the Continental Shelf
(Tunisia/​Libya) case: when Malta sought to nominate a judge ad hoc ‘for the purpose of
the intervention proceedings’, it was refused on ground that the would-​be intervener ‘has
no other right than to submit a request to be permitted to intervene, and has yet to es-
tablish any status in relation to the case’.338 At the same time, the Court rejected Malta’s

330
Land, Island and Maritime Frontier Dispute, Application by Nicaragua for Permission to Intervene,
Judgment, ICJ Reports (1990), pp. 92, 134, para. 99.
331
Ibid., p. 135, para. 102.
332
Cf. supra, MN 127.
333
Cf. supra, MN 87–​90.
334
Cf. also Kooijmans/​Bordin on Art. 31 MN 37–​41.
335
Preparation of the Rules of Court of January 30th, 1922, PCIJ, Series D, No. 2, pp. 177, 215.
336
In contrast ITLOS Rules of the Tribunal, ITLOS/​8, 25 September 2018, Rule 103, para. 4 states that an
intervening State party is not entitled to choose a judge ad hoc.
337
Wimbledon, PCIJ, Series C, No. 3, vol. I, pp. 118 et seq.
338
Continental Shelf (Tunisia/​Libya), Application by Malta for Permission to Intervene, ICJ Reports (1981),
pp. 3, 6, para. 8.

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 1736 Statute of the ICJ

request for the ad hoc judges appointed by the Parties not to sit during the proceedings
on the admissibility of intervention.
134 In the Land, Island and Maritime Frontier Dispute case, in rejecting Nicaragua’s
claim that its request to intervene should be heard by the full Court,339 and not by
the Chamber selected by El Salvador and Honduras, the Court reiterated the pos-

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ition that a State requesting intervention has no status at that stage in the proceed-
ings.340 A number of judges dissented on various grounds. Allowing a Chamber to
determine a request for intervention was thought to constitute a denial to the third
State of the right to have its request to intervene judicially considered in the usual
way.341 It was pointed out that of the five judges appointed to the Chamber, only
two were permanent members of the Court. Both El Salvador and Honduras had
appointed a judge ad hoc, and although the term of office of the fifth, the President
of the Chamber, had expired, he continued to sit in accordance with Article 17 of
the Rules of Court.342 Further, El Salvador and Honduras had put their views on the
selection of judges to the Chamber. A decision of a Chamber has the authority of a
decision of the Court. This combination of circumstances emphasizes most strongly
the disadvantaged status of an intervening State. It has no input into the composition
of the Chamber,343 must see its application considered by a Chamber ‘all of whose
five members it is reasonably entitled to feel have been practically hand-​picked by the
existing Parties’,344 and has no recourse to the full Court, or any other judicial tri-
bunal. Further, the Court allowed no oral proceedings to enable Nicaragua to make
its arguments on this point.
135 However, the procedural rights of intervening States are restricted both before and
after a request is granted. The rejection of Nicaragua’s application to have its request
heard by the full Court, or to reform the Chamber, highlights its non-​party status,
while the autonomy of the parties in the presentation of their case to a forum whose
composition they had selected was enhanced. Any inclusion of a third State into
proceedings commenced by other States impacts upon the parties’ formulation and
presentation of their case, and the Court has ensured that this impact is kept to the
minimum.

339
Cf. supra, MN 19.
340
Land, Island and Maritime Frontier Dispute, Application for Permission to Intervene, Order of
28 February 1990, ICJ Reports (1990), pp. 3, 5. The Court had acceded to the parties’ request for a
Chamber and their choice of judges in its Order of 8 May 1987 in the same case, Constitution of Chamber,
ICJ Reports (1987), pp. 10 et seq. Cf. also Lauterpacht, Administration of Justice, pp. 87–​98, as well as
Zimmermann, ‘Bemerkungen zum Verhältnis von ad hoc-​Kammern des Internationalen Gerichtshofes und
Intervention—​Die Entscheidung im Streitfall vor dem IGH zwischen El Salvador und Honduras’, ZaöRV
50 (1990), pp. 646–​60.
341
Land, Island and Maritime Frontier Dispute, Application for Permission to Intervene, Order of 28
February 1990, Diss. Op. Shahabuddeen, ICJ Reports (1990), pp. 18 et seq.
342
Cf. Palchetti on Art. 26 MN 35.
343
Judge Tarassov said of the intervening State that ‘its procedural position before a Chamber is not on a par
with the position of the initial parties. Such an inequality might be especially harmful to the intervening party
if it were to seek reformation of the existing composition of a Chamber or a modification of that Chamber’s
mandate’. Land, Island and Maritime Frontier Dispute, Application for Permission to Intervene, Order of 28
February 1990, Diss. Op. Tarassov, ICJ Reports (1990), pp. 11–​3.
344
Ibid., Diss. Op. Shahabuddeen, ICJ Reports (1990), p. 19.

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 Article 62 1737

H. Intervention in Other Fora

Despite the uncertainties and ambiguities in Article 62, similar provisions have been in- 136
cluded in other conventions that provide for a permanent forum for international adjudica-
tion. The situation is however different in respect to arbitration.

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Article 31 of the Statute of the ITLOS provides for intervention in similar terms to Article 137
62.345 There is no requirement that the intervening State must have accepted the Tribunal’s
jurisdiction under Article 287 of the UNCLOS.346 However, there is a final para. to Article
31 that clarifies the position with respect to the binding nature of the judgment on the
intervening State. Article 31, para. 3 states that ‘[i]‌f a request to intervene is granted, the de-
cision of the Tribunal in respect of the dispute shall be binding upon the intervening State
Party in so far as it relates to matters in respect of which that State Party intervened’.
Article 10 of the WTO Understanding on Rules and Procedures Governing the 138
Settlement of Disputes347 deals with procedures for third members by providing when
such a member may make submissions and the procedures to be followed. It states:
1. The interests of the parties to a dispute and those of other Members under a covered
agreement at issue in the dispute shall be fully taken into account during the panel
process.
2. Any Member having a substantial interest in a matter before a panel and having
notified its interest to the DSB (referred to in this Understanding as a ‘third party’)
shall have an opportunity to be heard by the panel and to make written submissions
to the panel. These submissions shall also be given to the parties to the dispute and
shall be reflected in the panel report.
3. Third parties shall receive the submissions of the parties to the dispute to the first
meeting of the panel.
4. If a third party considers that a measure already the subject of a panel proceeding nulli-
fies or impairs benefits accruing to it under any covered agreement, that Member may
have recourse to normal dispute settlement procedures under this Understanding.
Such a dispute shall be referred to the original panel wherever possible.
The WTO has taken a much less restrictive approach to participation by third parties in
proceedings before it than has the ICJ. It has been argued that this liberal stance stems
from the fact of compulsory jurisdiction in the WTO dispute settlement procedures.348
Article 36, para. 1 of the European Convention on Human Rights349 gives the right to 139
an applicant’s State of nationality to submit written comments and to take part in hear-
ings (unless of course that State is the defendant). Article 36, para. 2 allows ‘in the interest
of the proper administration of justice’ the President of the Court to invite a State party
to the Convention that is not a party to the proceedings or ‘any person concerned’ to

345
Annex VI UNCLOS. See also Rules of the Tribunal, ITLOS/​8, 25 September 2018, Rules 99–​104. For
a brief comment see Staker, ‘Annex VI. Article 31: Request to Intervene’, in United Nations Convention on the
Law of the Sea: A Commentary (Proelss, ed., 2017), pp. 2430–​34.
346
Cf. Art. 99, para. 3 of the Rules of ITLOS.
347
Annex 2 of the Agreement Establishing the World Trade Organization, 15 April 1994, 1867 UNTS 3,
1867 UNTS 154.
348
Iwasawa, JIEL (2002), pp. 287–​305.
349
4 November 1950, ETS No. 5.

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 1738 Statute of the ICJ

submit written comments and take part in hearings.350 Article 5, para. 2 of the Protocol
to the African Charter on Human and Peoples’ Rights on the establishment of an African
Court on Human and Peoples’ Rights allows a State party with an interest in the case to
submit a request to the Court to be permitted to join the case.351
140 In all these cases, intervention is provided for by the Statute of the permanent

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adjudicatory body, and this is in line with the idea of statutory jurisdiction and the in-
cidental nature of the proceedings. The situation is different in arbitration. Normally,
the statute of the arbitral body is constituted by the special agreement creating it. Thus,
it would seem logical that intervention in arbitral procedures would only be possible
with the parties’ consent or by an extensive interpretation by the tribunal of its inherent
powers.352 As Professor Abi-​Saab put it in 1999 before the Institute of International Law,
‘[t]‌he constitution of ad hoc tribunals is totally controlled by the Parties. The question of
intervention does not arise except to the extent they allow it in the jurisdictional title’.353
141 In practice, special agreements on inter-​state arbitration rarely have specific provisions
on intervention.354 And if they refer for application to the PCA Rules, one must note that
the 2012 Arbitration Rules do indeed provide for the possibility of a third (State or pri-
vate party) to intervene, but as a form of alternative to the introduction of a new case and
the joining of the two connected proceedings.355 By contrast, the PCA Optional Rules for
Arbitrating Disputes between Two States do not contain any provision on intervention.
142 The situation may arise when arbitration is instituted under a general convention, like
for instance, the 1928 General Act of Arbitration (Pacific Settlement of International
Disputes),356 whose Article 36 allows for intervention in the terms of Article 62 of the
PCIJ Statute ‘in judicial or arbitral procedure’. But this is an exceptional provision, with
no equivalent in other multilateral conventions providing for adjudication. Thus, Annex
VII UNCLOS on arbitration contains no provision on intervention (whereas the statute
of ITLOS does). The question arises whether intervention by a third State is possible in
this case.357 It has been raised, to some extent, before the Arbitral Tribunal in the South
China Sea Arbitration, where a number of States, Vietnam in particular, expressed inter-
ests in the dispute.358 Even if Vietnam was granted access to some elements of the written

350
The latter part of the provision refers to the possibility of hearing an amicus curiae. No such provision
exists in the ICJ Statute. Cf. Dupuy/​Hoss on Art. 34 MN 39–​41.
351
10 June 1998, OAU Doc. OAU/​LEG/​EXP/​AFCHPR/​PROT(III).
352
Discussing this inherent power related to the good administration of justice, under the form of an enquiry
over general principles of procedural law, the Guano Case (Chile/​France) (1901), RIAA, vol. XV, pp. 77–​387, 315.
353
‘Reply of Mr. Georges Abi-​Saab (18 July 1995)’, Annu. de l’Inst. de Droit Internat. 68-​I (1999), p. 161.
354
The situation of mixed arbitral tribunals is different (cf. Amerasinghe, Jurisdiction of International
Tribunals (2003), pp. 314–​22).
355
Cf. Art. 17, para. 5 of the 2012 PCA Arbitration Rules: ‘The arbitral tribunal may, at the request of any
party, allow one or more third persons to be joined in the arbitration as a party provided such person is a party
to the arbitration agreement, unless the arbitral tribunal finds, after giving all parties, including the person or
persons to be joined, the opportunity to be heard, that joinder should not be permitted because of prejudice
to any of those parties. The arbitral tribunal may make a single award or several awards in respect of all parties
so involved in the arbitration.’
356
26 September 1928, 93 LNTS 343.
357
Forteau, ‘Third-​Party Intervention as a Possible Means to Bridge the Gap between the Bilateral
Nature of Annex VII Arbitration and the Multilateral Nature of UNCLOS’, in The Rule of Law in the Seas of
Asia: Navigational Chart for Peace and Stability—​International Symposium on the Law of the Sea (Ministry of
Foreign Affairs of Japan, ed., 2015), pp. 160–​74. For a negative view, see Treves, in Fabri/​Sorel (2005), p. 75.
358
This concerns both the States having a particular claim over some of the maritime features (see supra, fn.
204) or more generally, States having an interest in the interpretation of Art. 121 UNCLOS.

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 Article 62 1739

procedure, the ‘Tribunal stated that it would address the permissibility of intervention in
these proceedings “only in the event that Viet Nam in fact makes a formal application for
such intervention”.’359 It did not, and the answer to the question whether intervention is
possible in arbitral proceedings, in the absence of a statutory provisions or in the absence
of consent of the parties, remains open.

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I. Evaluation
The poor legislative history, the decision taken in 1922 not to attempt to resolve the dif- 143
ficult issues of Article 62 in the Rules of Court but to leave them to be decided in the
circumstances of the cases as they arose, and the subsequent ad hoc nature of the case
law have all inhibited the emergence of ‘any coherent body of judicial authority in this
important area of procedural law’.360 Provision for third States to participate in proceed-
ings before the ICJ is restrictive and the Court has not interpreted Article 62 and Rule
81 in an expansive way. The rejection of the applications to intervene by Costa Rica and
Honduras indicates that the apparently greater willingness to allow intervention that was
seen in the acceptance of the requests of Nicaragua and Equatorial Guinea has not been
maintained, at least in land and maritime disputes. The Court reverted to its earlier re-
strictive jurisprudence on the admissibility of requests to intervene. It has also reduced
the motivation for intervention in maritime boundary disputes by avoiding demarcation
in overlapping areas. However, acceptance by the Court of Greece’s request to intervene
by fifteen votes to one may indicate that the Court is more receptive to intervention in
non-​boundary disputes.
Nevertheless some issues remain outstanding. Although the Court has clarified that 144
intervention is a case of statutory jurisdiction over incidental proceedings, and thus de-
termined that an intervening State does not have to establish a jurisdictional link, it also
paved the way to confusion, by creating two categories of intervention under Article
62: intervention as a party and intervention as a non-​party. This distinction, of little im-
pact in practice, obscures both the conditions and the purposes of intervention.
Consequently, intervention under Article 62 ranges among the divisive issues, and the 145
judges regularly make proposals for amending the Rules.361 The favoured approach to-
wards intervention in international adjudication depends upon the way in which various
conflicting principles are reconciled in the context of the particular case. As was recog-
nized long ago, on the one hand a restrictive approach preserves party autonomy in the
integrity of the dispute, while a broader approach fosters the harmonious development of
the law and allows third parties influence in the development of the law. In particular, in
determining its response to a request to intervene, the Court has to balance the interests
of the parties in the integrity of their dispute as submitted to the Court against those of
the third State in protecting what it perceives as its interest. Allowing intervention means
that the case differs from that presented to the Court by the parties, but denying third

359
South China Sea Arbitration (Philippines v. China), PCA Case No. 2013-​19, Award of 12 July 2016,
para. 43.
360
Pulau Ligitan, Application by the Philippines for Permission to Intervene, Sep. Op. Weeramantry, ICJ
Reports (2001), p. 630, para. 2.
361
Territorial and Maritime Dispute, Application by Honduras for Permission to Intervene, Diss. Op.
Donoghue, ICJ Reports (2011), pp. 471, 491–​2, para. 59. See also ibid., p. 484, para. 35.

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 1740 Statute of the ICJ

States access to the Court risks upholding party autonomy at the expense of third States’
interests.
146 Nevertheless, despite its long history, the Court has remained reluctant to extend inter-
vention. This is the case even though intervention under Articles 62 and 63 are the only
procedures open to third States under the Court’s contentious jurisdiction and these

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procedures are limited to States.362 The Court has also been unwilling to accept amicus
curiae briefs even from States in its contentious jurisdiction, although both States and
international organizations may furnish information to the Court under its advisory jur-
isdiction, according to Article 66, para. 2.
147 This being said, the Internet partially changed the picture. It gave States the oppor-
tunity to informally transmit to the Court (or, for the matter, to an arbitral tribunal)
their legal position on matters before it. It has become usual for official legal notes to be
posted on official websites, in the course of proceedings. The South China Sea Arbitration
is a topical case of excessive informal communications. Even if these documents do not
become part of the proceedings, they are generally considered by the judges or even
taken into account. There is good and bad in these informal briefs. For an international
court or tribunal, they are a supplementary source of information. At the same time,
they are completely outside the institutional and procedural framework, which contains
rules protective of the sincerity of the proceedings and, as such, are essential to the good
administration of justice. These documents may appear late in the proceedings (since,
under Article 56 of the Rules they would be considered as readily available), and this
lateness would not allow the Parties to consider them thoroughly and discuss them in an
adversarial manner. Moreover, since they are not part of the proceedings, their probative
value may not be appreciated on an objective basis. This is obviously problematic if they
were to influence the decision, one way or the other. How does this relate to intervention
proceedings? Since ultimately the function of intervention is to inform the Court of the
legal interests of third States, informal amicus curiae briefs are both a way to circumvent
the high threshold set out for intervention and the few legal consequences arising from it.
For the third State, the act of intervention becomes a political gesture, taking position on
a legal matter, in a solemn and highly publicized manner.

alina miron christine chinkin

362
Miller has proposed that intervention should be made available for other international actors; Miller, in
Gross, The Future of the ICJ, pp. 550, 560.

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