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Courts in recent years have perceived threshold obstacles to the enforcement of treaties deriving from their nature as contracts between nations that generally depend for their efficacy on the interest and honor of the parties, rather than on domestic adjudication. This approach to treaty enforcement is in tension with the Constitution’s declaration that treaties are part of the law of the land and its instruction to judges to give them effect. The Founders understood that treaties depended on interest and honor on the international plane, but they made treaties enforceable in our courts anyway in order to avoid the international friction that could be expected to result from treaty violations and to capture the benefits of a reputation for treaty compliance. The Supremacy Clause gives treaties a domestic judicial sanction that they would otherwise lack. It makes treaties enforceable in the courts in the same circumstances as the other two categories of norms specified in the clause—federal statutes and the Constitution itself.

The sole exception to this rule is for treaties that are non-self-executing in the sense contemplated by the Court in Foster v. Neilson. The concept of a non-self-executing treaty fits uneasily with the Supremacy Clause, as reflected in the common but untenable view that non-self-executing treaties lack the force of domestic law. According to Foster, a non-self-executing treaty is not enforceable in the courts because it is addressed to the political branches. But determining which treaties are so addressed has been challenging. Treaties generally leave the question of domestic implementation to the domestic laws of the states-parties, and our domestic law (the Supremacy Clause) directs judges to give them effect. The author argues that the Supremacy Clause establishes a default rule that treaties are directly enforceable in the courts like other laws, rebuttable only by a clear statement that the obligations imposed by the treaty are subject to legislative implementation.

If the stipulation had to appear in the text of the treaty, the clear statement rule would present problems for U.S. treaty makers seeking to control the domestic consequences of multilateral treaties. To address this problem, the treaty makers have developed a new form of clear statement, the “declaration” of non-self-execution. However, scholars have questioned the compatibility of such declarations with the Supremacy Clause. The author concludes that the treaty makers have the power to limit the domestic effects of treaties through declarations of non-self-execution. On the other hand, if the Constitution were understood to establish a default rule of non-self-execution, declarations of self-execution would stand on more tenuous ground. Thus, a default rule of self-execution is not only more consistent with the constitutional text and structure and with Supreme Court precedent, it is also normatively attractive because it leaves the treaty makers with the power to control the domestic consequences of the treaties they conclude.

Publication Citation

122 Harv. L. Rev. 599-695 (2008)