Subsequent Agreements and Subsequent Practice in Relation to the Interpretation of Treaties

A/RES/73/202View PDF

Who adopted this document and its mandates?

A Resolution of the General Assembly, under agenda item 82 Report of the International Law Commission on the work of its 70th session, published in 2019.

What subjects does this mandate have?

4 subjects

International Organizations Law of Treaties Treaties Treaty Interpretation

What’s in this document?

4 operative paragraphs

Welcomes the conclusion of the work of the International Law Commission on subsequent agreements and subsequent practice in relation to the interpretation of treaties, and its adoption of the draft conclusions and commentaries thereto;²

²Ibid., para. 52.

Expresses its appreciation to the International Law Commission for its continuing contribution to the codification and progressive development of international law;

Takes note of the statements in the Sixth Committee on the subject, including those made at the seventy-third session of the General Assembly,³ after the International Law Commission had completed its consideration of this topic in accordance with its statute;

³See A/C.6/73/SR.20, A/C.6/73/SR.21, A/C.6/73/SR.22, A/C.6/73/SR.23, A/C.6/73/SR.24, A/C.6/73/SR.29 and A/C.6/73/SR.30; see also the statements in the Sixth Committee that are available on the United Nations PaperSmart portal.

Also takes note of the conclusions on subsequent agreements and subsequent practice in relation to the interpretation of treaties, the text of which is annexed to the present resolution, with the commentaries thereto, brings them to the attention of States and all who may be called upon to interpret treaties, and encourages their widest possible dissemination.

Subsequent agreements and subsequent practice in relation to the interpretation of treaties

Part One

Introduction

Conclusion 1

Scope

The present conclusions concern the role of subsequent agreements and subsequent practice in the interpretation of treaties.

Part Two

Basic rules and definitions

Conclusion 2

General rule and means of treaty interpretation

Articles 31 and 32 of the Vienna Convention on the Law of Treaties set forth, respectively, the general rule of interpretation and the recourse to supplementary means of interpretation. These rules also apply as customary international law.

A treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to its terms in their context and in the light of its object and purpose, as provided in article 31, paragraph 1.

Article 31, paragraph 3, provides, inter alia, that there shall be taken into account, together with the context, (a) any subsequent agreement between the parties regarding the interpretation of the treaty or the application of its provisions; and (b) any subsequent practice in the application of the treaty which establishes the agreement of the parties regarding its interpretation.

Recourse may be had to other subsequent practice in the application of the treaty as a supplementary means of interpretation under article 32.

The interpretation of a treaty consists of a single combined operation, which places appropriate emphasis on the various means of interpretation indicated, respectively, in articles 31 and 32.

Conclusion 3

Subsequent agreements and subsequent practice as authentic means of interpretation

Subsequent agreements and subsequent practice under article 31, paragraph 3 (a) and (b), being objective evidence of the understanding of the parties as to the meaning of the treaty, are authentic means of interpretation, in the application of the general rule of treaty interpretation reflected in article 31.

Conclusion 4

Definition of subsequent agreement and subsequent practice

A subsequent agreement as an authentic means of interpretation under article 31, paragraph 3 (a), is an agreement between the parties, reached after the conclusion of a treaty, regarding the interpretation of the treaty or the application of its provisions.

A subsequent practice as an authentic means of interpretation under article 31, paragraph 3 (b), consists of conduct in the application of a treaty, after its conclusion, which establishes the agreement of the parties regarding the interpretation of the treaty.

A subsequent practice as a supplementary means of interpretation under article 32 consists of conduct by one or more parties in the application of the treaty, after its conclusion.

Conclusion 5

Conduct as subsequent practice

Subsequent practice under articles 31 and 32 may consist of any conduct of a party in the application of a treaty, whether in the exercise of its executive, legislative, judicial or other functions.

Other conduct, including by non-State actors, does not constitute subsequent practice under articles 31 and 32. Such conduct may, however, be relevant when assessing the subsequent practice of parties to a treaty.

Part Three

General aspects

Conclusion 6

Identification of subsequent agreements and subsequent practice

The identification of subsequent agreements and subsequent practice under article 31, paragraph 3, requires, in particular, a determination whether the parties, by an agreement or a practice, have taken a position regarding the interpretation of the treaty. Such a position is not taken if the parties have merely agreed not to apply the treaty temporarily or agreed to establish a practical arrangement (modus vivendi).

Subsequent agreements and subsequent practice under article 31, paragraph 3, may take a variety of forms.

The identification of subsequent practice under article 32 requires, in particular, a determination whether conduct by one or more parties is in the application of the treaty.

Conclusion 7

Possible effects of subsequent agreements and subsequent practice in interpretation

Subsequent agreements and subsequent practice under article 31, paragraph 3, contribute, in their interaction with other means of interpretation, to the clarification of the meaning of a treaty. This may result in narrowing, widening, or otherwise determining the range of possible interpretations, including any scope for the exercise of discretion which the treaty accords to the parties.

Subsequent practice under article 32 may also contribute to the clarification of the meaning of a treaty.

It is presumed that the parties to a treaty, by an agreement or a practice in the application of the treaty, intend to interpret the treaty, not to amend or to modify it. The possibility of amending or modifying a treaty by subsequent practice of the parties has not been generally recognized. The present conclusion is without prejudice to the rules on the amendment or modification of treaties under the Vienna Convention on the Law of Treaties and under customary international law.

Conclusion 8

Interpretation of treaty terms as capable of evolving over time

Subsequent agreements and subsequent practice under articles 31 and 32 may assist in determining whether or not the presumed intention of the parties upon the conclusion of the treaty was to give a term used a meaning which is capable of evolving over time.

Conclusion 9

Weight of subsequent agreements and subsequent practice as a means of interpretation

The weight of a subsequent agreement or subsequent practice as a means of interpretation under article 31, paragraph 3, depends, inter alia, on its clarity and specificity.

In addition, the weight of subsequent practice under article 31, paragraph 3 (b), depends, inter alia, on whether and how it is repeated.

The weight of subsequent practice as a supplementary means of interpretation under article 32 may depend on the criteria referred to in paragraphs 1 and 2.

Conclusion 10

Agreement of the parties regarding the interpretation of a treaty

An agreement under article 31, paragraph 3 (a) and (b), requires a common understanding regarding the interpretation of a treaty which the parties are aware of and accept. Such an agreement may, but need not, be legally binding for it to be taken into account.

The number of parties that must actively engage in subsequent practice in order to establish an agreement under article 31, paragraph 3 (b), may vary. Silence on the part of one or more parties may constitute acceptance of the subsequent practice when the circumstances call for some reaction.

Part Four

Specific aspects

Conclusion 11

Decisions adopted within the framework of a Conference of States Parties

A Conference of States Parties, under these conclusions, is a meeting of parties to a treaty for the purpose of reviewing or implementing the treaty, except where they act as members of an organ of an international organization.

The legal effect of a decision adopted within the framework of a Conference of States Parties depends primarily on the treaty and any applicable rules of procedure. Depending on the circumstances, such a decision may embody, explicitly or implicitly, a subsequent agreement under article 31, paragraph 3 (a), or give rise to subsequent practice under article 31, paragraph 3 (b), or to subsequent practice under article 32. Decisions adopted within the framework of a Conference of States Parties often provide a non-exclusive range of practical options for implementing the treaty.

A decision adopted within the framework of a Conference of States Parties embodies a subsequent agreement or subsequent practice under article 31, paragraph 3, in so far as it expresses agreement in substance between the parties regarding the interpretation of a treaty, regardless of the form and the procedure by which the decision was adopted, including adoption by consensus.

Conclusion 12

Constituent instruments of international organizations

Articles 31 and 32 apply to a treaty which is the constituent instrument of an international organization. Accordingly, subsequent agreements and subsequent practice under article 31, paragraph 3, are, and subsequent practice under article 32 may be, means of interpretation for such treaties.

Subsequent agreements and subsequent practice of the parties under article 31, paragraph 3, or subsequent practice under article 32, may arise from, or be expressed in, the practice of an international organization in the application of its constituent instrument.

Practice of an international organization in the application of its constituent instrument may contribute to the interpretation of that instrument when applying articles 31 and 32.

Paragraphs 1 to 3 apply to the interpretation of any treaty which is the constituent instrument of an international organization without prejudice to any relevant rules of the organization.

Conclusion 13

Pronouncements of expert treaty bodies

For the purposes of these conclusions, an expert treaty body is a body consisting of experts serving in their personal capacity, which is established under a treaty and is not an organ of an international organization.

The relevance of a pronouncement of an expert treaty body for the interpretation of a treaty is subject to the applicable rules of the treaty.

A pronouncement of an expert treaty body may give rise to, or refer to, a subsequent agreement or subsequent practice by parties under article 31, paragraph 3, or subsequent practice under article 32. Silence by a party shall not be presumed to constitute subsequent practice under article 31, paragraph 3 (b), accepting an interpretation of a treaty as expressed in a pronouncement of an expert treaty body.

This conclusion is without prejudice to the contribution that pronouncements of expert treaty bodies make to the interpretation of the treaties under their mandates.

Who adopted this document and its mandates?

What subjects does this mandate have?

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