Afroyim v. Rusk

Afroyim (plaintiff), a naturalized U.S. citizen who immigrated from Poland, voted in an Israeli parliamentary election in 1951. When he later applied to renew his U.S. passport, the government (defendant, the Secretary of State) denied it under a federal statute stripping citizenship from any citizen who votes in a foreign election. Afroyim sued for a declaratory judgment that the statute was unconstitutional; the lower courts upheld the statute under Congress's power over foreign affairs.