Part IV The Regimes of the Sources of International Law, s.XXIV Sources of International Trade Law, Ch.48 Sources of International Trade Law: Understanding What the Vienna Convention Says About Identifying and Using ‘Sources For Treaty Interpretation’
Donald H. Regan
Edited By: Jean d'Aspremont, Samantha Besson
- International trade — Vienna Convention on the Law of Treaties — General principles of international law — Sources of international law
International trade law is overwhelmingly treaty-based. For practical purposes, the unique traditional ‘source’ of WTO law is the WTO treaty. But treaties require interpretation, and there are many controversial questions about what might be called the ‘sources for treaty interpretation’. What materials can be used to interpret a treaty, and how are they to be used? The standard source for answering these questions, especially in the WTO, is the Vienna Convention on the Law of Treaties (VCLT). This chapter discusses a fundamental, and largely overlooked, question about the structure of the VCLT—the rationale of the distinction between Articles 31 and 32 of the VCLT. The answer is central to understanding the individual provisions of these Articles.