Missouri v. Holland
U.S. Case Law
252 U.S. 416 (1920), held that Congress may enact legislation to fulfill the terms of a treaty, even if such legislation otherwise constitutes an invasion of individual state sovereignty. The state of Missouri had sought to preserve exclusive authority over its game laws by enjoining U.S. game wardens from enforcing the Migratory Bird Treaty Act of 1918, which obligated Canada and the United States to protect certain migratory species. The Supreme Court disallowed the injunction, arguing that Congress must be able to act in the national interest, even if by means of unpopular legislation pursuant to an international treaty.