By: Gary Born, Danielle Morris & Stephanie ForrestPDF
The margin of appreciation is an ill-defined legal concept that some international tribunals have referred to when affording a measure of deference to actions taken by national authorities. As most international tribunals have concluded, however, the margin of appreciation is neither a rule of international law nor a justifiable exercise of adjudicative authority in the vast majority of cases. International law and interna- tional adjudication are better served by a more analytically rigorous approach that eschews references to a margin of appreciation; tribunals should be guided by the text, object and purposes of the relevant treaty provisions and applicable rules of international law. Consistent with this analysis, international tribu- nals have either refused to apply a margin of appreciation or only paid lip service to the concept, while proceeding to conduct an objective review of the state’s compliance with its international law obligations.
The Article first considers the origins, early applications and subsequent rejection of the margin of appreci- ation doctrine by international courts and tribunals, including the International Court of Justice and its predecessor, the Permanent Court of International Justice. Early applications of a margin of appreciation were rare and generally limited to exceptional circumstances where a measure of deference to decisions of national authorities, international organizations or tribunals was mandated by treaty language, object and purpose. Part II then goes on to consider the only context in which the margin has been applied with any frequency—before the European Commission on Human Rights and the European Court of Human Rights. While the application of the margin of appreciation in that setting is subject to significant criticism, its application in the European human rights context is arguably justified by the text, object and purposes of the European Convention on Human Rights and the unique historical, legal and cultural setting in which the Strasbourg bodies operate.
Despite the doctrine’s rejection elsewhere, a handful of investment tribunals have transposed the margin of appreciation from the European human rights context into international investment law. Part III argues that, in these few instances, the margin has been applied by tribunals without meaningful explanation of the doctrine’s relevance and without regard to the historical development—and limitations—of the doctrine. The Article concludes by arguing, in Parts IV and V, that there is no generally applicable margin of appreciation in international investment law or international law more generally. The Article argues instead for an approach that takes into account the text, object and purposes of investment treaties and gives effect to the rules of international investment law and international law more generally.