Paolo Gabriel D.
Jamer
I. Invalidity
Generally speaking, the validity and continuance in force of a treaty
and of consent to be bound is presumed but various matters may give rise to
issues of invalidity. Invalidity may be relative where a treaty is voidable if a
party establishes certain grounds or absolute where the treaty is void per se.
Issues of invalidity tend to arise rarely in practice.1
II. Error
As provided in Vienna Convention of Law of Treaties of Article 48, a
state may invoke an error as invalidating its consent to a treaty if the error
relates to a fact or situation which was assumed by that State to exist at the
time when the treaty was concluded and formed an essential basis of its
consent to be bound by the treaty. However, consistent with the previous
law, Article 48(2) provides that this does not apply if the State in question
contributed by its own conduct to the error or if the circumstances were such
as to put that State on notice of a possible error.2
III. Fraud
There are few helpful precedents. The Vienna Convention of Law of
Treaties provides that a state which has been induced to enter into a treaty by
the fraud of another negotiating state may invoke the fraud as invalidating its
consent to be bound by the treaty. Fraudulent misrepresentation of a material
fact inducing an essential error is dealt with by the provision relating to
error.3
IV. Coercion
Coercion includes coercion of state representatives144 and of states
themselves. Article 51 of the Vienna Convention of Law of Treaties, it
provides that ‘the expression of a State’s consent to be bound by a treaty
which has been procured by the coercion of its representative through acts or
threats directed against him shall be without legal effect. The concept of
coercion extends to blackmailing threats and threats against the
representative’s family.4
V. Jus Cogens
It means a compelling law. Article 53 of the Vienna Convention of
Law of Treaties, provides that a treaty is void if at the time of its conclusion
it conflicts with a peremptory norm of general international law. Further, a
1
Crawford, J. (n.d.). Brownlie’s Principles of Public International Law (8th ed., Vol. 1). Oxford.
2
Ibid
3
Ibid
4
Ibid
treaty becomes void if it conflicts with a peremptory norm of general
international law established after the treaty comes into force.5
VI. Termination of Treaties
A treaty may be terminated or suspended according to the terms of the
treaty or with the consent of the parties. There are three modes of
terminating a treaty which are: (a) material breach; (b) impossibility of
performance; and (c) change of fundamental conditions (rebus sic
stantibus).6
(a) Material Breach
It is widely recognized that material breach by one party entitles
the other party or parties to a treaty to invoke the breach as the
ground of termination or suspension. This option by the wronged
party is accepted as a sanction for securing the observance of
treaties. However, considerable uncertainty has surrounded the
precise circumstances in which such right of unilateral abrogation
may be exercised, particularly in respect of multilateral treaties.7
(b) ) Impossibility of Performance
The Vienna Convention of Law of Treaties provides that a party
‘may invoke the impossibility of performing a treaty as a ground
for terminating it if the impossibility results from the permanent
disappearance or destruction of an object indispensable for the
execution of the treaty.8
(c) Rebus Sic Stantibus
The principles by which fundamental change of circumstances
may be invoked as a ground for terminating or withdrawing from a
treaty are expressed in Article 62 of the Vienna Convention of
Law of Treaties. An example would be the case where a party to a
military and political alliance, involving exchange of military
intelligence and information, has a change of government
incompatible with the basis of alliance. The provision reflects the
doctrine of rebus sic stantibus, which involves the implication of a
term that the obligations of an agreement would end if there had
been a change of circumstances.9
5
Crawford, J. (n.d.). Brownlie’s Principles of Public International Law (8th ed., Vol. 1). Oxford.
6
Bernas. (2009). Introduction to Public International Law. Rex Printing Company, Inc.
7
Crawford, J. (n.d.). Brownlie’s Principles of Public International Law (8th ed., Vol. 1). Oxford.
8
Ibid
9
Ibid
