livered in an auditorium in Chicago under the auspices of the Christian Veterans of America. The meeting commanded considerable public attention. The auditorium was filled to capacity with over eight hundred persons present. Others were turned away. Outside of the auditorium a crowd of about one thousand persons gathered to protest against the meeting. A cordon of policemen was assigned to the meeting to maintain order; but they were not able to prevent several disturbances. The crowd outside was angry and turbulent.
Petitioner in his speech condemned the conduct of the crowd outside and vigorously, if not viciously, criticized various political and racial groups whose activities he denounced as inimical to the nation's welfare.
The trial court charged that "breach of peace" consists of any "misbehavior which violates the public peace and decorum"; and that the "misbehavior may constitute a breach of the peace if it stirs the public to anger, invites dispute, brings about a condition of unrest, or creates a disturbance, or if it molests the inhabitants in the enjoyment of peace and quiet by arousing alarm." Petitioner did not take exception to the instruction. But he maintained at all times that the ordinance as applied to his conduct violated his right of free speech under the Federal Constitution. . . .
The argument here has been focused on the issue of whether the content of petitioner's speech was composed of derisive, fighting words, which carried it outside the scope of the constitutional guarantees. See Chaplinsky v. New Hampshire, 315 U.S. 568; Cantwell v. Connecticut, 310 U.S. 296, 310. We do not reach that question, for there is a preliminary question that is dispositive of the case.
As we have noted, the statutory words "breach of the peace" were defined in instructions to the jury to include speech which "stirs the public to anger, invites dispute, brings about a condition of unrest, or creates a disturbance. . . ." That construction of the ordinance is a ruling on a question of state law that is as binding on us as though the precise words had been written into the ordinance. . . .
The vitality of civil and political institutions in our society depends on free discussion. As Chief Justice Hughes wrote in De Jongc v. Oregon, 299 U.S. 353, 365, it is only through free debate and free exchange of ideas that government remains responsive to the will of the people and peaceful change is effected. The right to speak freely and to promote diversity of ideas and programs is therefore one of the chief distinctions that sets us apart from totalitarian regimes.
Accordingly a function of free speech under our system of government is to invite dispute. It may indeed best serve its high purpose when it induces a condition of unrest, creates dissatisfaction with conditions as they are, or even stirs people to anger. Speech is often provocative and challenging. It may strike at prejudices and preconceptions and have profound unsettling effects as it presses for acceptance of an idea. That is why freedom of speech, though not absolute, Chaplinsky v. New Hampshire, supra, pp. 571-572, is nevertheless protected against censorship or punishment, unless shown likely to produce a clear and present danger of a serious substantive evil that rises far above public inconvenience, annoyance, or unrest. See Bridges v. California, 314 U.S. 252, 262; Craig v. Harney, 331 U.S. 367, 373. There is no room under our Constitution for a more restrictive view. For the alternative would lead to standardization of ideas either by legislatures, courts, or dominant political or community groups.