Necessity in International Investment Law: Some Critical Remarks on CMS v Argentina

The economic measures adopted by Argentina during the grave crisis that afflicted the country at the turning of the century have generated a stream of disputes with foreign investors in which Argentina tried to justify these measures on grounds of necessity. This article discusses the decisions of the Arbitral Tribunal and the ad hoc Committee in CMS v Argentina, focusing on the conditions imposed by the Argentina-United States bilateral investment treaty and by customary international law, as well as on the relationship between the two sources. It also briefly addresses the question of the alleged self-judging character of the relevant article of the treaty and the issue of compensation.