Looking for Legitimate Claims: Scope of Nafta Chapter 11 and Limitation of Responsibility of Host State

The lack of a political or legal filter for investor claims makes it necessary for host States to look at new means to dismiss frivolous or illegitimate claims. No solution to this problem is readily offered by the law of treaties or the law of State responsibility. Nevertheless, public international law does frame the discussion on the limitation of host State responsibility. Attempts have been made to use the provisions on the field of application of North American Free Trade Agreement (NAFTA) to achieve this objective. First attempt was made to consider NAFTA chapters on investment and other issues as mutually exclusive. A second attempt, by using the concept of 'measures relating to foreign investors or their investments' in NAFTA Article 1110, has been more successful. The chapter examines these overlooked attempts to use provisions on the scope of treaties in the quest for legitimate claims in international investment law. Keywords:Host State; international investment law; North American Free Trade Agreement (NAFTA)