in J Chaisse & TY Lin (eds), International Economic Law and Governance (OUP 2016) ch 8
Introduction: Professor Mitsuo Matsushita has shown an abiding interest in the systemic problems faced by the multilateral trading system. I recall his interventions on GATT Article XX and, in particular, his keen interest in the challenges posed by regional trade agreements (RTAs). He has spoken often about the RTA problem during events held by the Asia WTO Research Network over the past decade. This tribute to him discusses Article 31 (1) (3) (c) of the Vienna Convention on the Law of Treaties (VCLT), or the ‘systemic integration clause’, in light of his concerns.
Article 31 (3) (c) has been discussed in the WTO jurisprudence. Panels and the Appellate Body have occasionally had to address questions about the integration of the WTO legal order with WTO Members’ other international legal obligations. But – with some notable exceptions – it is an issue that could benefit from greater attention still. Such benign neglect may be questioned, since this clause could provide a broader approach to external norms than Article XX’s General Exceptions Clause in resolving conflicts between WTO and non-WTO treaties, and between WTO treaty norms and a whole range of non-treaty-derived norms. The utility of the clause in dealing with conflicts between WTO and RTA rules has been a subject of special neglect.
The Vienna Convention’s ‘systemic integration clause’, as we shall call it, read together with the Appellate Body’s famous pronouncement in US – Gasoline that the GATT is not to be read in clinical isolation from public international law, deserves close attention as the multilateral trading system continues to grapple with non-trade regulatory issues and the increasing complexity of the WTO’s interrelationship with the RTAs. However, while the existence and applicability of the systemic integration clause in the WTO acquis has been acknowledged and upheld by the Appellate Body, the full manner in which it could be ‘operationalized’ to borrow Philippe Sands’ terminology, remains a matter of conjecture. Part of that difficulty lies as I have said in an incomplete exploration of the clause itself in the trade literature, but it also lies in the clause’s very narrow application thus far in the WTO’s case law.