Customary International Law: Its Nature, Sources and Status as Law of the United States

Customary international law is one of the primary components of law in the international legal process, a dynamic process profoundly interconnected with our own domestic legal processes for at least the last 250 years. In our history, customary international law has also been received as part of the “law of nations,” a phrase used interchangeably by our courts with the phrase “international law” from the dawn of the United States. What, more particularly, has been the perceived nature of customary international law in the United States? Despite much theoretical discussion (usually without adequate attention to actual trends in judicial decision), what have been recognizable sources or evidences of that law and its components? What constitutional bases exist for the incorporation of customary international law, and what sorts of status are possible? These and related questions are explored in this article.