I'm nothing but a trial judge in one federal court.... I don't run the universe, and I have nothing to do with international affairs.(1)
Consider the above quote from a federal district court judge in light of the following: In the early 1990s, members of an Algerian fundamentalist group brutally raped and tortured several Algerian women in Algeria.(2) In addition, the group butchered and summarily executed friends and family members of the women in Algeria.(3) When the Algerian military government banned the fundamentalist group, one of the group's members fled to the United States, sought political asylum, and conducted business on behalf of the group from Washington, D.C.(4) The Algerian women then brought suit against the group in the United States District Court for the District of Columbia, alleging that the actions taken against them, their friends, and their family members in Algeria constituted violations of international law.(5)
Despite the fact that the alleged events described above took place in Algeria, concerned only Algerian citizens, and involved a claim of a violation of international law, a United States district court had jurisdiction over the case under the Alien Tort Claims Act (ATCA).(6) provides: "The district courts shall have original jurisdiction of any civil [tort] action by an alien ... committed in violation of the law of nations or a treaty of the United States."(7) Rather than claiming a violation of a treaty to which the United States was a party, the Algerian women based their ATCA claim on a violation of the "law of nations.(8)
Ascertaining whether a violation of the "law of nations" has occurred involves delving into the territory of "customary international law,"(9) a growing body of law that includes norms that emerge when "conduct, or the conscious abstention from certain conduct, of states ... becomes in some measure a part of [the] international legal order."(10) Determining the scope of customary international law is often difficult. Although the Restatement (Third) of the Foreign Relations Law of the United States(11) ("Restatement") and a few federal court cases(12) provide clarification and reinforce the authority of customary international law in U.S. courts, ambiguities remain. The Restatement itself acknowledges some of this uncertainty: "No definition of customary law has received universal agreement.... Each element in attempted definitions has raised difficulties. There have been philosophical debates about the very basis of the definition: how can practice build law?"(13)
The ambiguities inherent in defining and using customary international law have sparked heated debates regarding its use, particularly in international human rights claims in domestic courts.(14) On one side of the debate are those who maintain that U.S. courts have a responsibility to enforce and uphold international law, and should continue to do so even when deciding a claim requires the courts to make difficult customary international law findings.(15) On the other side are critics who argue that the ambiguities of customary international law are too great, that U.S. courts lack the authority to "find" customary international law, and that letting them do so offends federalism and separation of powers principles.(16) For example, some critics assert that customary international law is unenforceable in U.S. courts without an explicit congressional authorization.(17) An increase in the number of international human rights cases reaching federal courts,(18) and the recent trend toward loosening the requirements of and decreasing the time necessary for establishing customary norms,(19) have intensified the customary international law debate and imposed urgency on the need to resolve it.
Almost a century ago, in The Paquete Habana,(20) the Supreme Court acknowledged that "[i]nternational law is part of our law, and must be ascertained and administered by the courts of justice of appropriate jurisdiction. …