Conflicting rules and clashing courts: the case of multilateral environmental agreements, free trade agreements and the WTO

With an ever increasing number of international agreements addressing a wide range of issues, clashes between such agreements and international courts have become more likely if not avoidable. Whether it concerns the relation of labour law and competitiveness, climate change mitigation and tariffs on environmental goods and services, the protection of the sea and maritime transportation, or biodiversity conservation and the green economy - trade law and with it the WTO touches upon a myriad of areas regulated by international agreements other than the WTO.

Professor Pieter Jan Kuijper from Amsterdam University explores this relation in his recent study "Conflicting Rules and Clashing Courts: The Case of Environmental Agreements, Free Trade Agreements and the WTO" published by the International Centre for Trade and Sustainable Development (ICTSD). In this paper, the tool kit available under international law to solve such disputes is discussed through a large number of references to exiting or potential cases.
Professor Kuijper concludes his paper with a list of concrete recommendations to negotiators, litigators, courts and countries. Amongst others, he proposes increased attention on the principle of mutual supportiveness - an wording found in an increasing number of environmental agreements. Moreover, he makes some concrete observations on so called "fork-in-the-road provisions" in free trade agreements and develops recommendations for the inter-regime coordination of international tribunals and the application of comity or litispendence in international courts:

"The application of WTO law may require that the interpretative principle of mutual supportiveness is applied to the relevant WTO rules, which does not imply non-application of WTO law, but application in a restrained way that would not harm the object and purpose of the WTO Agreements."

"In the interest of the stability of international rule making and governance, international courts and tribunals in neighboring fields, like trade, investment, the environment etc. need to develop a doctrine of "forum non conveniens" between themselves, or at the very least use their inherent powers to abstain from exercising jurisdiction or rule on admissibility if there are serious reasons to do so."