American Communications Association v. Douds, 339 U.S. 382 (1950), is a 5-to-1 ruling by the United States Supreme Court which held that the Taft–Hartley Act's imposition of an anti-communist oath on labor union leaders does not violate the First Amendment to the United States Constitution, is not an ex post facto law or bill of attainder in violation of Article One, Section 10 of the United States Constitution, and is not a "test oath" in violation of Article Six of the Constitution.