Changing Times, Changing Obligations? The Interpretation of Treaties over Time

Abstract

International treaties often reflect long-term agreements that are difficult to amend. For instance, we see difficulty associated with amending United Nations Charter, despite longstanding calls for institutional reform. We also see stalemate with Doha Round of trade negotiations, where disagreements between developed and developing countries have prevented amendment to WTO obligations to further reduce trade barriers. It is in this that I suggest we look to treaty interpretation tools to adapt treaties to evolving circumstances. In particular, conduct of treaty parties subsequent to conclusion of a treaty allows an interpreter to gauge how parties intend to apply treaty obligations to changing times and circumstances. My remarks address (1) framework for interpreting treaties; (2) how treaty interpretation can be used to adopt an evolved interpretation of treaty terms; and (3) distinction between an evolved treaty interpretation and treaty modification. FRAMEWORK FOR TREATY INTERPRETATION It is generally accepted that Articles 31-33 of Vienna Convention reflect customary principles of treaty Article 31(1) requires interpretation to be undertaken in good faith, in accordance with ordinary meaning of treaty terms in their and in light of their object and purpose. Article 31(2) defines in further detail meaning of context. Article 31(3) requires that together with context interpreter take into account (a) any subsequent agreement between parties regarding interpretation of treaty or application of its provisions; (b) any subsequent practice in application of treaty which establishes agreement of parties regarding its interpretation; (c) any relevant rules of international law applicable in relations between parties. Within Article 31 there is no interpretative hierarchy. It was envisioned by International Law Commission (ILC) that the application of means of interpretation in article would be a single combined operation. All various elements, as they were present in any given case, would be thrown into crucible, and their interaction would give legally relevant interpretation. (1) Of provisions mentioned above, Articles 31(3)(a) and (b), in particular, offer possibility to adopt an evolved interpretation of treaty terms. Both articles require an interpreter to take into account subsequent conduct of treaty parties where such conduct demonstrates an agreement as to interpretation of treaty terms. In this regard, distinction between Articles 31(3)(a) and (b) is more formalistic than substantive. A formal written agreement between parties agreeing to meaning of an otherwise ambiguous term would likely fall within Article 31(3)(a). On other hand, independent actions of both parties, temporally separated, that appear to demonstrate agreement between them on meaning of treaty are more likely to come within Article 31(3)(b). There is a spectrum of conduct between these two, and in this regard, Articles 31(3)(a) and (b) can be seen to be on a continuum, with former requiring a higher evidentiary threshold. (2) That continuum also represents weight to be accorded to party agreement for purposes of treaty The stronger case for conduct to come within Article 31(3)(a), more weight that should be given to conduct as expressing an authentic interpretation of text. EVOLUTIVE APPROACH TO TREATY INTERPRETATION Are there any boundaries to parties' ability to agree to an evolved interpretation of treaty terms? In his work on subject with ILC, Professor Georg Nolte has noted that treaties can change over time, must adapt to new situations, and evolve according to social needs of international community. …