In the 1989 case Texas v. Johnson, the US Supreme Court ruled in a 5-4 decision that the act of burning an American flag is constitutionally-protected free speech under the First Amendment.
The petitioner in the case, Gregory Lee Johnson, was prosecuted and convicted for violating Texas’ law against flag desecration when he burned a flag outside Dallas City Hall in protest of former President Ronald Reagan.
After a Texas appeals court overturned his conviction, the state of Texas appealed to the Supreme Court, which ruled in Johnson’s favor.
In a separate 1990 decision, the Supreme Court also ruled that federal legislation criminalizing flag burning a crime violates the constitution. In United States v. Eichman, the Court struck down the 1989 Flag Protection Act, which made burning or destroying an American flag a federal crime.