Integration of Judicial Decisions in Multiple Proceedings before the WTO and RTAS: the Potential Relevance of Article 32 of the VCLT

In the last several decades there has been an exponential growth in the number of Regional Trade Agreements (RTAs). In addition to creating a wide overlap of substantive rights and obligations with the World Trade Organisation, many RTAs are also equipped with legalized dispute settlement mechanisms, which operate independently from the compulsory, automatic and exclusive system of WTO dispute settlement. This parallel of substantive commitments and legalised mechanisms may potentially result in conflicts of jurisdiction where a single dispute is submitted simultaneously or consecutively to both fora. It has been well addressed in various studies that if such conflicts arise, there is currently no legal rule that can satisfactorily determine which forum should have jurisdiction. As a result, multiple proceedings appear unavoidable. This article seeks to offer a new way to look into the jurisdictional tension between the WTO and RTAs. It will be argued that in the absence of effective rules to determine jurisdictional priority, Article 32 of the Vienna Convention on the Law of Treaties may provide a practical and useful technique to minimise the negative consequences of multiple proceedings, i.e. inconsistent interpretations and findings over essentially the same disputes.