Texas v. Johnson (1989)
During the 1984 Republican National Convention, Gregory Lee Johnson protested political and corporate policies by burning an American flag outside Dallas City Hall. He was convicted under a Texas law that prohibits the desecration of respected objects. The Supreme Court ruled that a deliberately expressive nonverbal act can be defined as speech; therefore, if it does not disturb the peace, it is protected by the First Amendment. These words are from the majority opinion written by William Brennan. The the full text here.