Self‐Execution and Treaty Duality

Abstract

The Supremacy Clause of the U.S. Constitution states that, along with the Constitution and laws of the United States, treaties made by the United States are part of the supreme Law of the Land. At least since the Supreme Court's 1829 decision in Foster v. Neilson, however, it has been understood that treaty provisions are enforceable in U.S. courts only if they are self-executing. The legitimacy and implications of this self-execution requirement have generated substantial controversy and uncertainty among both courts and commentators. This Article attempts to clear up some of the conceptual confusion relating to the self-execution doctrine and, in the process, better explain the contemporary practice of the courts and political branches relating to treaty enforcement. To that end, the Article makes three claims. First, the Supremacy Clause does not by itself tell us the extent to which treaties should be judicially enforceable. Second, the relevant intent in discerning self-execution is the intent of the U.S. treatymakers (that is, the President and Senate), not the collective intent of the various parties to the treaty. Third, even if treaties and statutes have an equivalent status in the U.S. legal system in the abstract, there are important structural and functional differences between them that are relevant to judicial enforceability. These three claims are interconnected in that each of them reflects the fact that treaties have a dual nature, operating both within the domain of international politics as well as within the domain of law, a feature that is in turn relevant to the scope of their domestic judicial enforceability. The three claims are also complementary, in that each of them is best understood along with the other two, and together they present a relatively coherent explanation for the precedent and practice in the area. The Article concludes by discussing how the Supreme Court's recent decision in Medellin v. Texas, despite certain ambiguities, is generally consistent with the three claims.