Enforcement of the WTO 'regional exceptions' : a comparative institutional analysis

The increasing number of Preferential Trade Agreements (PTAs) gives rise to tensions with the multilateral trading system because they collide with the most important principle of the WTO legal order: non-discrimination. More precisely, PTAs bear the risk of running afoul of Member States’ most favoured nation obligations. To mitigate this conflict, WTO law provides for rules governing the formation of PTAs. However, the content of these rules is far from being undisputed and their application is subject to various institutional constraints. In this contribution I shall analyse the institutions charged with administering the law governing the WTO consistency of PTAs and compare their advantages and drawbacks. On this basis I shall explain why the WTO ‘regional exceptions’ remain largely unenforced. To that end, I focus on the ‘costs’ of participating in the processes of legality scrutiny