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H. General principles of treaty law

a. CONCEPTS

“Treaty” – means an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation. (Article 1[a], 1969 Vienna Convention on the Law of Treaties)

“Ratification”, “acceptance”, “approval” and “accession” – mean in each case the international act so named whereby a State establishes on the international plane its consent to be bound by a treaty. (Article 1[b], Ibid.)

“Full powers” – means a document emanating from the competent authority of a State designating a person or persons to represent the State for negotiating, adopting or authenticating the text of a treaty, for expressing the consent of the State to be bound by a treaty, or for accomplishing any other act with respect to a treaty. (Article 1[c], Ibid.)

“Reservation” – means a unilateral statement, however phrased or named, made by a State, when signing, ratifying, accepting, approving or acceding to a treaty, whereby it purports to exclude or to modify the legal effect of certain provisions of the treaty in their application to that State. (Article 1[d], Ibid.)

“Negotiating State” – means a State which took part in the drawing up and adoption of the text of the treaty. (Article 1[e], Ibid.)

“Contracting State” – means a State which has consented to be bound by the treaty, whether or not the treaty has entered into force. (Article 1[f], Ibid.)

“Party” – means a State which has consented to be bound by the treaty and for which the treaty is in force. (Article 1[g], Ibid.)

“Third State” – means a State not a party to the treaty. (Article 1[h], Ibid.)

“International organization” – means an intergovernmental organization. (Article 1[i], Ibid.)

1) Capacity of States to conclude treaties

Every State possesses capacity to conclude treaties.  (Article 6, Ibid.)

2) Full powers

1) A person is considered as representing a State for the purpose of adopting or authenticating the text of a treaty or for the purpose of expressing the consent of the State to be bound by a treaty if:

(a) he produces appropriate full powers; or

(b) it appears from the practice of the States concerned or from other circumstances that their intention was to consider that person as representing the State for such purposes and to dispense with full powers. (Article 7[1], Ibid.)

2) In virtue of their functions and without having to produce full powers, the following are considered as representing their State:

(a) Heads of State, Heads of Government and Ministers for Foreign Affairs, for the purpose of performing all acts relating to the conclusion of a treaty;

(b) heads of diplomatic missions, for the purpose of adopting the text of a treaty between the accrediting State and the State to which they are accredited;

(c) representatives accredited by States to an international conference or to an international organization or one of its organs, for the purpose of adopting the text of a treaty in that conference, organization or organ. (Article 7[2], Ibid.)

3) Subsequent confirmation of an act performed without authorization

An act relating to the conclusion of a treaty performed by a person who cannot be considered under article 7 as authorized to represent a State for that purpose is without legal effect unless afterwards confirmed by that State. (Article 8, Ibid.)

4) Means of expressing consent to be bound by a treaty

The consent of a State to be bound by a treaty may be expressed by signature, exchange of instruments constituting a treaty, ratification, acceptance, approval or accession, or by any other means if so agreed. (Article 11, Ibid.)

5) Formulation of reservations

A State may, when signing, ratifying, accepting, approving or acceding to a treaty, formulate a reservation unless:

1) the reservation is prohibited by the treaty;

2) the treaty provides that only specified reservations, which do not include the reservation in question, may be made; or

3) in cases not failing under subparagraphs (a) and (b), the reservation is incompatible with the object and purpose of the treaty. (Article 19, Ibid.)

6) Acceptance of and objection to reservations

1) A reservation, an express acceptance of a reservation and an objection to a reservation must be formulated in writing and communicated to the contracting States and other States entitled to become parties to the treaty. (Article 20[1], Ibid.)

2) If formulated when signing the treaty subject to ratification, acceptance or approval, a reservation must be formally confirmed by the reserving State when expressing its consent to be bound by the treaty. In such a case the reservation shall be considered as having been made on the date of its confirmation. (Article 20[2], Ibid.)

3) An express acceptance of, or an objection to, a reservation made previously to confirmation of the reservation does not itself require confirmation. (Article 20[3], Ibid.)

4) The withdrawal of a reservation or of an objection to a reservation must be formulated in writing. (Article 20[4], Ibid.)

7) “Pacta sunt servanda”

Every treaty in force is binding upon the parties to it and must be performed by them in good faith. (Article 26, Ibid.)

8) Internal law and observance of treaties

A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty. This rule is without prejudice to article 46. (Article 27, Ibid.)

9) Invalidity of Treaties

Provisions of internal law regarding competence to conclude treaties

A State may not invoke the fact that its consent to be bound by a treaty has been expressed in violation of a provision of its internal law regarding competence to conclude treaties as invalidating its consent unless that violation was manifest and concerned a rule of its internal law of fundamental importance. (Article 46[1], Ibid.)

A violation is manifest if it would be objectively evident to any State conducting itself in the matter in accordance with normal practice and in good faith. (Article 46[2], Ibid.)

a) Specific restrictions on authority to express the consent of a State

If the authority of a representative to express the consent of a State to be bound by a particular treaty has been made subject to a specific restriction, his omission to observe that restriction may not be invoked as invalidating the consent expressed by him unless the restriction was notified to the other negotiating States prior to his expressing such consent. (Article 47, Ibid.)

b) Error

1) A State may invoke an error in a treaty as invalidating its consent to be bound by the 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. (Article 48[1], Ibid.)

2) Paragraph 1 shall 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. (Article 48[2], Ibid.)

3) An error relating only to the wording of the text of a treaty does not affect its validity; article 79 then applies. (Article 48[3], Ibid.)

c) Fraud

If a State has been induced to conclude a treaty by the fraudulent conduct of another negotiating State, the State may invoke the fraud as invalidating its consent to be bound by the treaty. (Article 49, Ibid.)

d) Corruption of a representative of a State

If the expression of a State’s consent to be bound by a treaty has been procured through the corruption of its representative directly or indirectly by another negotiating State, the State may invoke such corruption as invalidating its consent to be bound by the treaty. (Article 50, Ibid.)

e) Coercion of a representative of a State

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 any legal effect. (Article 51, Ibid.)

f) Coercion of a State by the threat or use of force

A treaty is void if its conclusion has been procured by the threat or use of force in violation of the principles of international law embodied in the Charter of the United Nations. (Article 52, Ibid.)

g) Treaties conflicting with a peremptory norm of general international law (“jus cogens”)

A treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of general international law. For the purposes of the present Convention, a peremptory norm of general international law is a norm accepted and recognized by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character. (Article 53, Ibid.)

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