Dennis v. United States, 341 U.S. 494 (1951), was a United States Supreme Court case relating to Eugene Dennis, General Secretary of the Communist Party USA. The Court ruled that Dennis did not have the right under the First Amendment to the United States Constitution to exercise free speech, publication and assembly, if the exercise involved the creation of a plot to overthrow the government. In 1969, Dennis was de facto overruled by Brandenburg v. Ohio.