Nothing is more antagonistic to the freedom of speech than a mob shouting a speaker into silence. For state officials to suppress speech merely because the audience is offended by the speaker's message is a violation of the first amendment. Although some lower courts have experimented with the notion of a heckler's First Amendment right, there is no place in our constitutional order for what harry kalven called the "heckler veto." The duty of the police, when the audience is hostile, is to protect the speaker so long as that is reasonably possible. Similarly, the potential hostility of an audience—even its potential violence—will not justify denying a license to meet or parade in a public forum.
When police protection is inadequate, however, and audience hostility poses an immediate threat of violence, the police may constitutionally order a speaker to stop, even though the speech does not amount to incitement to unlawful conduct, and is otherwise protected by the First Amendment. The Supreme Court so held in feiner v. new york (1951), a case involving no more than "some pushing, shoving and milling around" in an audience hostile to a speaker in a park. The principle retains vitality, although Feiner itself, on its facts, seems an insecure precedent.
The constitutionality of police action requiring someone to stop addressing a hostile audience depends on one form of the clear and present danger test: the police may not stop the speaker unless the threat of violence is immediate and police resources are inadequate to contain the threatened harm. Thus, if the speaker refuses to stop and is charged with breach of the peace, the court must look beyond the arresting officers' good faith—a point emphasized by the Supreme Court in Feiner—to the objective likelihood of violence. Appellate courts, too, in reviewing convictions in such cases, must closely examine lower courts' findings of fact. An important difference between Feiner and Edwards v. South Carolina (1963), where the Court reversed breach of peace convictions of civil rights demonstrators facing a hostile audience, lay in the Edwards Court's willingness to scrutinize the record and reject the state courts' findings of danger.
Kenneth L. Karst
Kalven, Harry, Jr. 1965 The Negro and the First Amendment. Pages 139–145. Columbus: Ohio State University Press.