Fighting words are, as first defined by the Supreme Court (SCOTUS) in Chaplinsky v New Hampshire, 315 U.S. 568 (1942), words which "by their very utterance, inflict injury or tend to incite an immediate breach of the peace. It has been well observed that such utterances are no essential part of any exposition of ideas, and are of such slight social value as a step to truth that any benefit that may be derived from them is clearly outweighed by the social interest in order and morality."
Fighting words are a category of speech that is unprotected by the First Amendment. Further, as seen below, the scope of the fighting words doctrine has between its creation in Chaplinsky and the Supreme Court's interpretation of it today.
Non-Exhaustive List of SCOTUS Cases Invoking the Fighting Words Doctrine
The following cases show some of the instances in which the Supreme Court has invoked the fighting words doctrine. As shown, the scope of the doctrine changes between various cases.
Terminiello v. City of Chicago (1949)
In Terminiello v. Chicago, 337 U.S. 1 (1949), the Supreme Court narrowed the scope of what constitutes fighting words. The Court found that words which produce a clear and present danger are unprotected (and are considering fighting words), but words which invite dispute and causes unrest are protected (and are not considered fighting words).
Feiner v. New York (1951)
In Feiner v. People of State of New York, 30 U.S. 315 (1951), the Supreme Court held that akin to the fighting words doctrine, an incitement to riot which creates a clear and present danger is also not protected by the First Amendment.
Texas v. Johnson (1989)
In Texas v. Johnson, 491 U.S. 397 (1989), the Supreme Court redefined the scope of the fighting words doctrine to mean words that are "a direct personal insult or an invitation to exchange fisticuffs." In the case, the Court held that the burning of a United States flag, which was considered symbolic speech, did not constitute fighting words.`
R.A.V. v. St. Paul (1992)
In R.A.V. v. City of St. Paul, 505 U.S. 377 (1992), the Supreme Court found that the "First Amendment prevents government from punishing speech and expressive conduct because it disapproves of the ideas expressed." Even if the words are considered to be fighting words, the First Amendment will still protect the speech if the speech restriction is based on viewpoint discrimination.