The First Amendment, however, does not protect certain limited categories of speech that are "utterly without redeeming social importance." . . . See also R.A.V. v. City of St. Paul, 505 U.S. 377, 382-83 (1992) (stating that "[f]rom 1791 to present . . . our society, like other free but civilized societies, has permitted restrictions upon the content of speech in a few limited areas, which are of such slight 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"). These categories include obscenity, Roth, 354 U.S. at 483, libel, Beauharnais v. Illinois, 343 U.S. 250, 266 (1952), and "fighting words," Chaplinsky v. New Hampshire, 315 U.S. 568, 571-73 (1942) [see below. —jed]. Child pornography is also one of these categories of speech. Ferber, 458 U.S. at 763-64.
The area of speech defined as clear and present danger was codified in the Supreme Court case Brandenburg v. Ohio in which the court ruled that a law may only forbid speech advocating illegal or violent actions if the speech is intended to incite or produce imminent lawless action and if the speech is likely to incite or produce such action. (Cavazos and Morin, p. 74) Fighting words are a continuation of the clear and present danger idea, and are defined as words which are so offensive and abusive that they are likely to "cause or incite immediate physical retaliation by the audience." (Cavazos and Morin, p. 76)