The Supremacy of International Law: A Reply to David Moore

The Supremacy of International Law: A Reply to David Moore

JURIST Guest Columnist Jordan Paust of the University of Houston Law Center says the theory that self-executing treaties are the only type of international law that is binding on states is based on an incorrect, revisionist account of US legal history…

Devising theory, marshaling it and sending it off to do battle by itself can be fun, even intellectually challenging. But calling it constitutional law, or law in any sense, is another matter. I have wondered why some who prefer what is clearly a minority theoretic construct regarding the role of international law in our domestic legal processes often declare that there is “debate” among law professors, as if that makes constitutional law. Fuller consideration of the revisionist viewpoint that is otherwise ably summarized by Professor David Moore allows one to see why the putative revisionists often note that they instigated a “debate.”

As one can identify from my previous essay, what revisionist debaters are up against are the overwhelming views of the founders and framers, the text and structure of the US Constitution, and predominant trends in judicial decision that stand unavoidably, and at times famously, in opposition to their minority revisionist preferences. Indeed, with respect to supremacy there are already at least 45 federal (mostly Supreme Court) and 45 state court decisions that have consistently recognized that states are bound by treaties and at least 19 federal (mostly Supreme Court) and 30 state court cases have consistently recognized that states are bound by customary international law. The cases also provide evidence of why the minority revisionist theory is radical and basically unmoored. What is a revisionist to do? Try to avoid the overwhelming views of the founders and framers, the text and structure of the Constitution, and predominant trends in judicial decisions. Avoid computer-assisted research of the more than three thousand cases using international law, especially the very cases on point, and say that some professors disagree.

At least Professor Moore admits that “the US Constitution binds states to follow international law” but, he argues, only if that law “qualifies as enforceable, preemptive federal law.” Whether or not this is so, the 64 federal and 75 state court cases addressed in my two studies clearly affirm that international law qualifies as “enforceable” and “preemptive” supreme federal law for the states. Professor Moore raises Foster v. Neilson to point out that some treaties, by their terms, are not capable of direct operation for certain purposes and are non-self-executing. This is correct, but this does not change the fact that non-self-executing treaties are still supreme law of the US for other purposes, given the fact that the Constitution expressly and unavoidably requires that “all” treaties, not merely some, shall be supreme law of the land and binding on the states. In one of the earliest Supremacy Clause cases, Ware v. Hylton, Justice Samuel Chase confirmed that “any” treaty shall be superior to the constitution and laws of any individual state. While on circuit in 1806, Justice Bushrod Washington concluded in Gordon v. Kerr that a seemingly non-self-executing treaty “is supreme” over a state constitution. And in 1854, the US attorney general declared that all treaties are supreme over the states, even treaties requiring “enactment of a statute to regulate the details.”

Professor Moore argues that Medellin v. Texas “confirms” that “states may enact laws inconsistent with non-self-executing treaties until those treaties are executed.” This is quite strange, however, for at least two reasons. First, the mere fact that a treaty is not directly operative for private plaintiffs in federal courts does not mean that it cannot be used defensively, have a restraining effect under the Supremacy Clause (which, according to the text, “all” treaties necessarily and expressly have), or be used more generally for federal preemption. It especially does not mean that states can violate any US treaty and thereby wreak havoc with US foreign relations. Clearly, as one of my prior studies demonstrates, the framers did not expect that our Constitution would ever allow states to violate US treaties, nor is such possible in view of the actual text of the Supremacy Clause and the 90 federal and state court cases that have been documented since.

Second, Medellin did not rule that states can violate non-self-executing treaties. Justice John Paul Stevens, while concurring, correctly noted that, because the states are bound under the Supremacy Clause, the obligation to execute is also partly that of the states:

Under the express terms of the Supremacy Clause, the United States’ obligation to “undertake to comply” … falls on each of the States as well as the Federal Government. One consequence … [is that] States must shoulder the primary responsibility…. Texas’ duty in this respect is all the greater … it is now up to Texas to prevent the breach.

This was also noted by Justice Stephen Breyer in his dissent, and he stressed the point recognized in Ware v. Hylton that our constitutional structure is intentionally different from that of our British ancestors. Texas was not free to violate US treaty law. It was bound by treaty law and was left generally free to choose how to execute it.

With respect to customary international law, which has been directly incorporated in hundreds of cases since the founding, Professor Moore gives no attention to the 19 federal and 30 state court decisions that have already recognized that the states are bound by customary international law. Instead, he focuses primarily on a case that had nothing to do with international law and did not even mention customary international law or the law of nations per dictumErie v. Tompkins. He gives a cursory reference to Sosa v. Alvarez-Machain, as if it accepted a radical revisionist theory that “customary international law norms are not federal law absent incorporation into domestic law.” Quite the contrary, Sosa rejected such an ahistorical and unmoored theory, though it was favored in a dissenting opinion by Justice Antonin Scalia that cited a few debaters but mistakenly focused on mere common law (which, my treatise notes, is far different than customary international law) and avoided the numerous cases addressing international law as well as the actual views of the founders and framers, including those regarding human rights. As the majority in Sosa rightly stressed: “For two centuries, we have affirmed that the domestic law of the United States recognizes the law of nations,” quoting Banco Nacional de Cuba v. Sabbatino, The Paquete Habana, and The Nereide.

Prior to Sosa, the landmark decision from the US Court of Appeals for the Second Circuit in Filartiga v. Pena-Irala had aptly addressed the same sort of theory thusly:

Appellees … [claim] that the law of nations forms a part of the laws of the United States only to the extent that Congress has acted to define it. This extravagant claim is amply refuted by the numerous decisions applying rules of international law uncodified in any act of Congress

In its decision, the Second Circuit cited Ware, The Paquete Habana, Sabbatino, Smith, The Nereide and Murray v. Schooner Charming Betsy. A famous recognition by the US Supreme Court in 1942, in Ex parte Quirin, is also informative:

From the very beginning of its history this Court has recognized and applied the law of war as including that part of the law of nations which prescribes … the status, rights and duties of enemy nations as well as of enemy individuals.

Of course, there was no statute incorporating the law of war for criminal sanctions until 1916 but, as documented in my study of customary international law, it has been directly part of the laws of the US since the founding. The opinions of Chief Justice John Jay and Justices James Wilson and James Iredell in Henfield’s Case, in 1793, also stand out among the numerous cases that have used customary international law directly as part of the “laws of the United States.”

These are partly why Section 111(1)-(3) of the Restatement (Third) of the Foreign Relations Law of the United States is decidedly on point with respect to the direct incorporation of customary international law as “law of the United States” that is “supreme over the law of the several States” and that courts “are bound to give effect to.” And they are supportive of Chief Justice John Marshall’s more specific affirmation in the 1810 case of Fletcher v. Peck that our judicial tribunals “are established… to decide on human rights.” Indeed, computer-assisted research of the cases, which is documented in my treatise, demonstrates the use of human rights in hundreds of cases throughout our history.

When Sosa stated that courts should only apply definable and generally accepted customary legal norms, it was addressing the admitted need to prove the existence and content of a customary norm, not a limitation of its reach if it is actually part of customary international law and, therefore, part of the supreme law of the US. The integrity of the Supreme Court as an institution and of a venerable legal process of more than 220 years would be seriously undermined if the Court would ever ignore the predominant views of the founders and framers, the text and structure of the Constitution and the rich history of the use of international law by the judiciary.

Jordan J. Paust is the Mike & Teresa Baker Law Center Professor at the University of Houston and author of the treatise International Law as Law of the United States (2 ed. 2003) and the two studies mentioned in his prior essay in Jurist.

Suggested citation: Jordan Paust, The Supremacy of International Law: A Reply to David Moore, JURIST – Forum, July 10, 2012,

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