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This article is a response to David L. Sloss, Executing Foster v. Neilson: The Two-Step Approach to Analyzing Self-Executing Treaties, 53 Harv. Int'l L L.J. 135 (2012).

David Sloss’s article, Executing Foster v. Neilson, is an important contribution to the literature on the judicial enforcement of treaties. The author agrees with much of it, as he agrees with much of Professor Sloss’ other writing on treaties. In particular, the author agrees that the two-step approach to treaty enforcement that Professor Sloss proposes is generally the right approach, and he agrees that the “intent-based” approach to the self-execution issue that Professor Sloss criticizes is highly problematic. But he disagrees with Professor Sloss about the source of this problematic approach.

The much-controverted question of treaty self-execution is widely understood to concern whether a treaty may be enforced directly by the courts or must instead await legislative implementation. Professor Sloss proposes a two-step analysis for addressing this question. The first step is to determine what the treaty obligates the United States to do. This is a question of treaty interpretation, to be answered through the application of the international law of treaty interpretation. The second step is to identify which domestic officials have the power and duty to enforce the obligation. This, Professor Sloss argues, is entirely a matter of U.S. domestic law, not a matter of treaty interpretation. Courts and commentators have fallen into error, and produced much confusion, by treating the second question as one of treaty interpretation, seeking an answer in the text of the treaty or in the parties’ intent. Professor Sloss notes that treaties seldom address the question of which domestic officials—legislative, executive, or judicial—are responsible for enforcing the treaty. Instead, treaty parties almost always leave that question to the domestic law of the states-parties.

The author states that Professor Sloss is entirely correct to note that seeking the answer to this question in the treaty itself is highly problematic. Although there is nothing in international law that prevents states from addressing that question in the treaty itself, the fact is that states almost never do so. Domestic officials take their cues from domestic law, and states have very different constitutional rules concerning the need for legislative implementation of treaties. In the United Kingdom and most nations of the British Commonwealth, treaties are never enforceable in the courts until they have been implemented by legislation. The constitutional law of other countries permits the direct judicial enforcement of some treaties but not of others. In the United States, for example, treaties that require the criminalization of conduct or the appropriation of money must be legislatively implemented because the Constitution has been interpreted to require a statute for those purposes. Because of the diversity of domestic constitutional rules on the question, states rarely, if ever, address the issue of domestic implementation in the treaties they conclude. Seeking an answer to the self-executing question in the treaty itself is thus, in Justice Breyer’s words, like “hunting [for] the snark.” No matter how hard they look, the courts will almost never find an answer there.

States instead leave the question to the domestic law of each state-party. The most relevant provision of our Constitution is the Supremacy Clause, which provides that “all Treaties” of the United States are “the supreme Law of the Land,” and instructs judges to give them effect. This clause, the author argues, was intended to reverse the British rule, which we would otherwise have inherited. It establishes that treaties in the United States do not, as a constitutional matter, always require implementing legislation, and it appears to establish that treaties are judicially enforceable in the same circumstances as constitutional and statutory provisions of like content. The first task for a court confronted with a treaty should thus be to identify the treaty’s content, which, as Professor Sloss argues, is a matter of treaty interpretation. The next step should to be to ask whether the obligation imposed by the treaty is one that would be judicially enforceable if it were found in a statute. Thus, as with statutes, a treaty would not be judicially enforceable if it were unconstitutional—for example, if it purported to accomplish something for which the Constitution requires a statute, such as criminalization of conduct or appropriation of money. Similarly, a treaty would not be judicially enforceable if it imposed an obligation requiring the exercise of political judgment. This category would include treaties that set forth aspirations or that contemplate the exercise of discretion requiring political judgment. But, as Professor Sloss correctly argues, a treaty imposing a non-discretionary duty of government to behave in a determinate way towards individuals should not generally give rise to questions regarding its judicial enforceability at the behest of such individuals.

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53 Harv. Int’l L.J. Online 213-225 (2012)