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customary international law, CIL, federal common law, foreign relations law


Response to: Anthony J. Bellia, Jr. & Bradford R. Clark, The Federal Common Law of Nations, 109 Colum. L. Rev. 1 (2009).

A.J. Bellia and Brad Clark have performed a valuable service for other scholars interested in foreign relations law and federal jurisdiction by collecting and illuminating—with their usual care and insight—the historical practice of both English and early American courts with respect to the law of nations. Their recent Article, The Federal Common Law of Nations, demonstrates that, while American courts have not generally treated customary international law (CIL) as supreme federal law, they have applied such law where necessary to vindicate the “perfect rights” of foreign nations. In so doing, American courts have protected the prerogatives of the political branches to “recognize foreign nations, conduct foreign relations, and decide momentous questions of war and peace.” Although Professors Bellia and Clark disavow any attempt “to settle all questions of how customary international law interacts with the
federal system,” they do suggest that their approach represents a middle ground between proponents of the “modern position” that CIL simply is federal common law and critics of that position, who insist that CIL may be applied by American courts only where it is incorporated into the domestic legal system through an affirmative act by the political branches.

This response makes three points. First, I quibble with the historical account offered by Professors Bellia and Clark on two minor, yet at least somewhat significant, grounds: The debate over reception of the common law at the federal Constitutional Convention shows greater early skepticism about judge-made common law than Bellia and Clark suggest; also, the jurisdictional provisions of Article III covering cases implicating foreign affairs were not intended fully to centralize power over such cases in federal courts because they left concurrent jurisdiction in the state courts. Second, I question the extent to which the Founding Era history is directly relevant to contemporary debates about how to treat CIL. Finally, I contend that what does the real work in the Bellia and Clark approach is simply constitutionally-grounded concerns about the separation of powers in foreign affairs cases, not anything about CIL per se. Their position thus reduces to the largely uncontroversial claim that federal courts may make federal common law to protect these
constitutionally-grounded federal interests, and they may sometimes draw the content of federal common law from international law.

Library of Congress Subject Headings

International relations, Customary international law, International customary law