University of Pennsylvania Journal of International Law

Publication Date

Spring 2024

First Page


Document Type



Judicial enforcement of U.S. international agreements has long puzzled courts and scholars. By building upon the Supreme Court’s 2008 Medellin opinion, the 4th Restatement of Foreign Relations Law’s Sections 310 and 311 adopted in 2018 make a significant advance in further distinguishing and clarifying how to determine whether a treaty is self-executing, whether it creates a private right of action, and the ramifications for judicial enforcement of those determinations. However, an examination of modern major international trade and investment agreements reveals that there are additional refinements and more to say on the topic than covered by the 4th Restatement.

First, the 4th Restatement only addresses these topics in the context of treaties, not all international agreements. Second, the 4th Restatement generalizes the ways in which a private party can use a self-executing agreement in U.S. courts, and does not necessarily account for situations in which the political branches have elaborated different (narrower) contours for self-execution. Third, the 4th Restatement should list the various domestic documents surrounding international agreements that might be examined in order to glean U.S. political branch intent on the issue of selfexecution. Fourth, the 4th Restatement should make clear that it is U.S. political branch (international agreement-maker) intent that governs not only self-execution but also private rights of action. Fifth, the 4th Restatement should make clear that in addition to precision and the obligatory nature of a treaty provision, courts should also look at whether the agreement’s text reveals an alternative enforcement mechanism at the international level, and whether other nations are giving the provision direct effect (socalled “reciprocity” factor) to glean U.S. political branch intent on the issues of self-execution and private right of action. Sixth, the 4th Restatement might consider provisions on Executive Branch enforcement of treaties, including the possibility of the United States having an inherent right of action to invalidate state laws inconsistent with international agreements, although there are complexities and conflicting signals on this possibility.