Prosecuting Offenses Against the Law of Nations in the United States

Abstract

Article 1, Section 8, Clause 10 of the American Constitution affords to federal courts universal jurisdiction to “define and punish Piracies and felonies committed on the high Seas, and Offenses against the Law of Nations.” The U.S. Supreme Court decided many years ago that if an offense against the law of nations is adequately defined in international law, Congress need not define that crime before a federal court can prosecute the same. Offenses against the law of nations would now-a-days be called customary-law crimes.

The central theme of this article is that if an international crime is more restrictively defined in federal legislation than in customary international law, federal courts retain their constitutional competence to prosecute the crime in instances covered by the customary-law definition even if the criminal conduct is not covered by the statutory definition of the crime. Federal legislation short of a constitutional amendment cannot derogate from the constitutional competence of courts to exercise universal jurisdiction over Offenses under the law of nations; and the customary-law definition of an offense is determined by international law and not by Congress. Since drafters of the Statute of the International Criminal Court decided to include only customary-law crimes in the subject-matter jurisdiction of the ICC, and the definitions of crimes that went into the ICC Statute, with one exception only, was accepted by general agreement, it can safely be concluded that the crimes within the jurisdiction of the ICC as defined in the ICC Statute are “Offenses against the law of nations.”