A self-executing treaty is a treaty which of its own force furishes a rule of municipal law for the guidance of municipal courts in deciding cases involving the rights of individuals.

Ordinarily treaties are simply agreements or contracts between two or more sovereignties, obligating them to carry out the mutual promises contained therein. But under our Constitution a treaty is of greater force. It may operate as a law, just like an act of Congress. But the constitutional provision is not mandatory. Not every treaty provision is necessarily a law. For example, a promise to secure the passage of legislation would not be a law.

Whether a treaty of its own force makes law depends on two considerations. First, can the rule in question be given the force of legislation without action by Congress; second, did the treatymakers intend that it should be self-executing? The scope of the treaty-making power independent of congressional action has been discussed long and thoroughly. This paper will be devoted only to the second question.