A deep puzzle lies at the heart of international law. It is “law” binding on the United States, and yet it is not always enforceable in the courts. One of the great challenges for scholars, judges, and practitioners alike has been to make some sense of this puzzle—some might call it a paradox—and to figure out when international law can be used in U.S. courts and when it cannot.
The Supremacy Clause in the U.S. Constitution would seem to solve this puzzle. It says, after all, that “Treaties made, or which shall be made, under the Authority of the United States, shall be supreme Law of the Land.” Yet early in the country’s history, the Supreme Court distinguished between treaties “equivalent to an act of the legislature”—and therefore enforceable in the courts—and those “the legislature should execute”—meaning they could not be enforced in the courts until implemented by Congress and the President. Thus began a cottage industry devoted to determining when international law was enforceable in the courts.
Just when scholars had more or less come to a settled understanding of the status of international law in the courts—or at least agreed to disagree—the Supreme Court reentered the fray. Beginning in the 1990s, foreign nationals convicted of capital offenses and sentenced to death had begun challenging their convictions on the grounds that the arresting authorities had violated the Vienna Convention on Consular Relations (Vienna Convention), which the United States had ratified, by failing to inform them that they had the right to contact their consulates. U.S. courts refused to provide the relief the foreign nationals sought, and two of the cases eventually made their way to the International Court of Justice (ICJ). That Court twice held that the United States had breached its obligations to its treaty partners by failing to notify the consulates of foreign nationals upon their arrest. In the second of these two cases, the Court held that the United States had violated the Vienna Convention by failing to inform fifty-one Mexican nationals of their rights under the Convention upon their arrest. The Court declared that the United States was obligated to provide the fifty-one individuals—including petitioner José Ernesto Medellín—“review and reconsideration of the conviction and sentence by taking account of the violation of the rights set forth in the Convention.”
Medellín returned to the U.S. courts to enforce the holding, seeking the review and reconsideration called for by the ICJ. The Texas courts refused—in part on the grounds that the ICJ’s decision was not directly enforceable in domestic courts. The U.S. Supreme Court surprised many observers by agreeing. In Medellín v. Texas, the Court reasoned that the treaties granting jurisdiction to the ICJ were non-self-executing and thus not enforceable unless implemented into law by Congress. They were, in other words, among those treaties the legislature must execute. Congress, of course, had not passed implementing legislation—probably because nearly everyone had long assumed that the treaties at issue were legally binding, making implementing legislation unnecessary.
A significant line in the decision was buried in the footnotes. In the now-famous third footnote, the Court endorsed a “background presumption” against finding that treaties confer private rights or private rights of action, even when they are self-executing. This represented a significant shift away from U.S. courts’ historical approach to interpreting treaties. Indeed, it effectively reversed what had, during most of the country’s history, been a background presumption in favor of finding treaties to confer private rights of action whenever they conferred private rights. The decision thus highlighted, and heightened, uncertainty surrounding the enforcement of treaties in the U.S. courts.
This Article examines the status of treaties in U.S. courts—and how the international legal commitments expressed in our treaties “come home”—in three interlocking steps. First, it seeks in Part I to provide an account of the legal and historical context of Medellín—examining both the case law that led up to the decision and how the lower courts have since responded. Even before the Supreme Court’s 2008 decision, much had changed in the way the courts enforced treaties created under Article II of the U.S. Constitution. During the first 170 years of U.S. history, courts generally applied a strong presumption that private litigants could use treaties to press their claims in court. That all began to change just after World War II, as international treaties—and international human rights treaties in particular—proliferated. Still, the old presumption remained in place for certain categories of treaties. Understanding this transformation enables a deeper appreciation of the impact Medellín is already having, and will likely have in the future, on the enforcement of international law in U.S. courts.
Second, the Article aims in Part II to place direct enforcement of international law through private rights of action into broader context in a second way—by looking at all the ways in which international law can be enforced in U.S. courts. The direct enforcement of treaties called into doubt in the wake of Medellín is only a part of the picture. Treaties are enforced in U.S. courts in several other ways as well—through what we term “indirect enforcement,” “defensive enforcement,” and “interpretive enforcement.” These other ways of enforcing international commitments in U.S. courts are often ignored in the scholarly literature about judicial enforcement of international law. Many scholars treat one or the other in isolation, but no one considers them as a whole. As a result, advocates and critics of international law alike have placed too much emphasis on the use of international law as a cause of action for private litigants. This, in turn, has caused them to overestimate Medellín’s likely effect on the enforcement of international law in U.S. courts.
Finally, in Part III, this Article considers steps that can be taken to increase the likelihood that treaties will continue to be enforced directly, even in a post-Medellín world. We offer three proposals for how each of the branches of the federal government can strengthen the enforcement of international law. First, Congress could pass legislation providing for the judicial enforcement of certain subsets of Article II treaties. Second, the President and Senate could adopt a clear statement rule for treaty ratification—a practice through which the President submits treaties to the Senate for ratification with clear statements about whether they are self-executing, and through which the clear statement becomes part of the treaty’s formal text or accompanying documents. Third, the executive branch could pursue direct enforcement of treaty obligations itself. Where treaties are clear that private litigants lack rights of action, the U.S. government could bring affirmative lawsuits against state and municipal agencies that refuse to comply with treaties, to enjoin those entities from activities that place the United States in violation of its international obligations.
Our proposals each offer a path toward more effective enforcement of Article II treaties in U.S. courts. They are only valuable, of course, if the United States has an interest in abiding by the international legal commitments it makes. We recognize that there is an ongoing debate about this proposition. Although proving the proposition that it is in the United States’s interest to abide by its international law commitments is not a goal of this Article, we note at least two reasons to believe it is true. First, when treaties provide reciprocal benefits, the United States clearly gains from the enforcement of the agreements by other parties to the treaty. Indeed, for the 4.5 million Americans who live overseas and the 60 million who traveled abroad last year—not to mention the U.S. businesses whose trillions of dollars in investments are protected by a variety of international treaties—the ability to enforce treaty-based rights abroad is essential. But other countries are less likely to observe their treaty obligations if the United States fails to live up to its side of the bargain. A private right of action is often the best way to guarantee this compliance, for the federal judiciary is in a unique position to press the political branches to honor the country’s international commitments, particularly when those commitments benefit individuals. Second, regardless of the value one may place on any given international agreement—or the benefit that the United States receives from that particular treaty—the United States has a broader and deeper interest in demonstrating its capacity to abide by the commitments it makes. Until the United States chooses to end an international legal commitment (which it ordinarily can do by simply providing notice to this effect), it is obligated to comply with the agreement as a matter of international law. Failure to comply with such obligations makes the United States a law violator potentially subject to sanctions and—likely most harmful of all—an unreliable treaty partner. For these reasons, even those who dislike or disapprove of particular international agreements should wish to see the United States live up to the commitments that it has made.