INTRODUCTION

 Jus cogens are a body of peremptory norms, from which no state is permitted to
derogate, through treaties, from.
 However, the scope and existence of jus cogens have been much debated, finally
culminating in Art 53 of the VCLT.

DEVELOPMENT OF JUS COGENS

 As a result of the regulation of States by international law, the concept of ‘national
sovereignty’ has undergone an evolution and today States are regulated by both their
own national rules together with the continually developing laws of the international
community
 It is immediately noteworthy that norms of jus cogens are not included specifically as
being a ‘formal’ source of international law.
 Before these norms can be properly placed among the ‘formal’ sources one must
identify both its evolution as a legal concept and the extent of international
recognition of its existence.

RECOGNITION OF THE CONCEPT OF JUS COGENS IN INTERNATIONAL LAW

Theoretical acceptance of the concept of Jus Cogens
 The notion was in fact first developed by the so-called ‘stoics’.
 For the Spanish theologians of the XVI century (recognized as being the founders of
modern international law), for Grotius and for other classical writers there existed
certain ‘principles’17 which amounted to a jus naturale necessarium (necessary
natural law).
 Wolff and Vattel stated that there existed “necessary law” which was natural to all
States and that all treaties and customs which contravened this ‘necessary law’ were
illegal.
 This was of course in the natural law tradition.
o Natural law was therefore interpreted as being a “necessary law which all
states are obliged to observe.
o It included a theory that there existed universally binding principles of law
“which could not be changed by anyone.”
 o They distinguished between jus naturale necessarium and jus voluntarium or
voluntary law, described as consent based law or law “created by the
presumed, express or tacit will of States.”
o What is imp is that they recognised that the latter can’t change the former.
o Even Bodin, often portrayed as the supporter of absolute sovereignty, said that
sovereignty doesn’t mean unlimited sovereignty, but within the laws of nature
and the law of nations.
 Following this era, the notion of a superior and binding law on the international
community (in general natural law theories) gradually began to disappear.
o We moved to the positive law doctrine – law is actually and specifically
enacted or adopted by proper authority for the government of an organized
jural society.
o As a result, for some years both the expressions jus cogens and jus
dispositivum disappeared.
o The overriding notion became rather the idea that international law was
created solely through the will of States and was therefore subject to neither
limitation nor restriction.
o Based on such interpretation in theory States could enter into treaties having
any object and purpose
 Jus cogens, though developed from natural law, is not the same as jus naturale.
o Natural law theory is based on a belief that there exist concepts exterior to and
above positive law.
o Jus cogens, on the other hand, form an integral part of ‘positive’ law itself and
are defined and recognized by international law.
 As will be seen, these norms are norms which are accepted and recognized by the
international community as norms from which no derogation is permitted.
 Thus, jus cogens come very much from intl law and the will of states itself.

Formal legal recognition of the concept of Jus Cogens

 The concept of peremptory norms was not ‘formally’ accepted in international law
until the latter half of 20th century, with positivism still dominating the thought.
o However, these ideas did not disappear.
 First as has been seen, academics continued to acknowledge the
existence of peremptory norms on an informal basis
  Oppenheim stated that there are customary grounds to
invalidate a treaty if they conflict with certain principles.
 Hall stated so too.
 Second, moves towards a more ‘formal’ recognition of this concept
within internationally binding instruments and jurisprudence began to
appear after World War One.
 Article 20.1 of the Covenant of the League of Nations [Judge
Schücking in Oscar Chin case said that this is pretty much
recognition of jus cogens only]
 Art 38(1)(c), ICJ
 ICJ in Reservations to the Convention on the Prevention and
Punishment of the Crime of Genocide.
 Then comes the discussion in Vienna, with a clear backdrop of declining positivism
and recognition of jus cogens.
o By 1969, the prevailing view was that there was something called jus cogens.
o The final report of H Waldock clearly supported the concept and laid down
guidelines too – pg. 7 and 8 of the PDF.
o In the Vienna conference, it was also clear that most states accepted this in
principle. They differed somewhat as to how they could be identified and
defined.
o Finally, art 53 was adopted with majority – 87 for, 8 against and 12 abstained
 Difficulties after Art 53
o The issue was now codification of all those rules which were to be categorised
as “jus cogens”.
o ILC in the Vienna report only said that there was no simple criterion to
determine which rules were jus cogens.
o Some delegations (such as the French) did say that the provision itself was far
too vague and hence did not vote for it
o However, it is now clear that Art 53 is also the very definition of jus
cogens.
 JUS COGENS IDENTIFIED
 Having considered the general definition of jus cogens in the VCLT the following are
identified as being the pre-requisites necessary for a norm to be ‘elevated’ to the
status of jus cogens:
o The norm must be a norm of general international law.
 Should bind most if not all states
 Shouldn’t be regional or local or particular countries.
o The norm must be “accepted and recognized by the international community
of States as a whole”
 Acceptance and recognition by the international community can be
either express or implied
 As pointed out by the Chairman of the Drafting Committee at the
Vienna Conference Mr. Yasseen, the words “as a whole” were added
to draft Article 50 by the ILC to try to avoid a situation whereby one
State could effectively veto a decision to designate a norm as
peremptory:
 It would be enough if a large majority of states did so.
 If one state or a small group of states did so, it won’t affect the
peremptory nature of the norm.
 Thus, most states should do this.
 Jus cogens can be drawn from the following identified sources of
international law:
 General treaties
o If provisions of a treaty are jus cogens, then they bind
non parties too.
 CIL
o A large portion of international law remains customary
in nature
o For certain authors norms of jus cogens are to be found
primarily in international custom (Mc Nair, Katz,
Tunkin, Sztucki – only CIL can create JC)
 GP
 o “The fact that all States consider that immoral
agreements (contra bonos mores) are not binding”, is a
general principle of law, as affirmed by Judge
Schücking in his individual opinion in The Oscar Chin
Case.
o The norm must be one from which no derogation is permitted and which can
be modified only by a subsequent norm of general international law of the
same character
 This is in fact the main identifying feature and ‘essence’ of a norm of
jus cogens.
 It is “easier to illustrate these rules than to define them.
 it is possible to draw a preliminary classification of norms that do not
permit derogation by inter-parties treaties or otherwise
 Norms which have a fundamental bearing on the behaviour of
the international community of States as a whole and from
which no derogation is permitted at all.
o Good faith
 Norms which are necessary for the stability of the international
juridical order, and general principles of law
o pacta sunt servanda
o res inter alios acta
 Norms referred to as having humanitarian objects and purposes
including certain principles of human rights and international
humanitarian law
 Norms of general interest to the international community as a
whole or to international public order
o the goals and aspirations set out in the preamble to the
Charter of the United Nations
o “Purposes and Principles” of the United Nations, as set
out in inter alia, Articles 1.2 and 2.1 – 2.4
 Norms which are binding on all new States even without their
consent as being established rules of the international
community
 o principles of the freedom of the high seas or
o the common heritage of mankind,
o the protection of the environment and
o respect for the independence of States
 All states have an interest in jus cogens norms. Hence owe states owes it to all states.
Hence comes in erga omnes.
o It should be noted however that although all norms of jus cogens are
enforceable erga omnes not all erga omnes obligations are jus cogens.
o Reparations for Injuries suffered in the Service of the United Nations,
Advisory Opinion

EXAMPLES OF JUS COGENS

 There are obvious risks in over use of the notion and consequently often attempts to
do so attract criticism.
o This is particularly so when for example attempts are made to exhaustively list
entire treaties as being jus cogens.
 We begin with the examples put forward by the ILC in its final report to the Vienna
Conference
o The ILC decided against the inclusion of specific examples of jus cogens in
the draft article forwarded to the Vienna Conference, due to scope for
confusion and scope of their work itself.
o However, they gave illustrative examples
 Principles of the Charter of the United Nations prohibiting the
unlawful use of force
 International laws that prohibit the performance of any other act
criminal under international law
 International laws that oblige States to co-operate in the suppression of
certain acts such as trade in slaves, piracy or genocide
 Fitzmaurice
o A feature common to them, or to a great many of them, evidently is that they
involve not only legal rules but considerations of morals and of international
good order.
 Italian delegation in the Vienna Conference gave some examples
 o rules of an absolute character being those which “protected the human person”
and “ensured the maintenance of peace and the existence and equality of
States.”
o human rights norms, such as acts contrary to certain laws of war, colonialism
and racial discrimination
 Polish delegation
o acts contrary to fundamental norms of the international community such as the
principle of the freedom of the high seas

EMERGING NORMS OF JUS COGENS

 Art 64
o If a new peremptory norm of general international law emerges, any existing
treaty which is in conflict with that norm becomes void and terminates.
 How can new concepts of jus cogens be ‘created’:
o The ILC pointed out that “a modification of a rule of jus cogens would today
most probably be effected through a general multilateral treaty.”
o this could also be applied with regard to the emergence of new norms of jus
cogens
o Similarly, such norms could emerge through the recognition of a new rule of
customary international law which is considered as being peremptory
o As a result, in theory it appears that it would be possible for a new
peremptory norm to constitute a totally new concept having no link with
a pre-existing peremptory norm as long as it was accepted and recognised
by the international community as a whole as such.
 It is very unlikely that a jus cogens norm is derogated from by another jus cogens
norm, though theoretically possible.
o Consequently, it is the case that an emerging norm of jus cogens will probably
only ever be recognised if it takes the form of a totally new concept, which is
accepted and recognised by the international community as a whole.
 THE INVALIDITY OF TREATIES VIOLATING JUS COGENS
 After considerable debate and discussion at the ILC it was finally concluded that a
treaty which conflicts with a peremptory norm of international law is void if and
because its object is identified as being illegal.
 A treaty which is void because of such illegality terminates independently of the will
of the parties to the treaty - it is considered invalid ipso jure ab initio.
 Articles 53 and 64 of the Vienna Convention (above) therefore provide as a general
principle that a treaty is or becomes void if it conflicts with either an existing
peremptory norm or an emerging peremptory norm, respectively.
 Termination “by reason of…conflict with a new rule of jus cogens…is a special case
of termination.”
 Although a treaty may terminate as a result of emerging jus cogens it does not, in
our view, become void, such that it is found to have been without legal effect.
o However, it is clear that certain of the legal consequences and the rights and
obligations flowing from the treaty which come into conflict with the new
norm cannot be maintained.
 Art 71 –
o 1. In the case of a treaty which is void under article 53 the parties shall:
 (a) eliminate as far as possible the consequences of any act performed
in reliance of any provision which conflicts with the peremptory norm
of general international law; and
 (b) bring their mutual relations into conformity with the peremptory
norm of general international law.
o 2. In the case of a treaty which becomes void and terminates under article 64,
the termination of the treaty:
 (a) releases the parties from any obligation further to perform the
treaty;
 (b) does not affect any right, obligation or legal situation of the parties
created through the execution of the treaty prior to its termination;
provided that those rights, obligations or situations may thereafter be
maintained only to the extent that their maintenance is not in itself in
conflict with the new peremptory norm of general international law.
