Appellee Harris, who had been indicted for violating the California Criminal Syndicalism Act, sued in the Federal District Court to enjoin appellant, the county District Attorney, from prosecuting him, contending that the Act is unconstitutional on its face and inhibits him in exercising his free speech rights. Appellees Dan and Hirsch, claiming that the prosecution of Harris would "inhibit" them from peacefully advocating the program of the political party to which they belonged, and appellee Broslawsky, a college professor, claiming that the prosecution made him "uncertain" as to whether his teaching and reading practices would subject him to prosecution, intervened as plaintiffs. All asserted that they would suffer irreparable injury unless a federal injunction was issued. A three-judge court, relying on Dombrowski v. Pfister, 380 U.S. 479, held the Act void for vagueness and overbreadth, and enjoined Harris' prosecution.
1. There is no basis for equitable jurisdiction based on the allegations of appellees other than Harris, who have not been indicted, arrested, or threatened with prosecution, and the normal course of a state criminal prosecution cannot be blocked on the basis of fears of prosecution that are merely speculative. Pp. 41-42.
2. Federal courts will not enjoin pending state criminal prosecutions except under extraordinary circumstances where the danger of irreparable loss is both great and immediate in that (unlike the situation affecting Harris) there is a threat to the plaintiff's federally protected rights that cannot be eliminated by his defense against a single prosecution. The decision in Dombrowski, supra, which involved alleged bad faith harassment and is factually distinguishable from this case, does not substantially broaden the availability of injunctions against state criminal prosecutions. Pp. 43-54.
281 F.Supp. 507, reversed. [p38]
BLACK, J., delivered the opinion of the Court, in which BURGER, C.J., and HARLAN, STEWART, and BLACKMUN, JJ., joined. STEWART, J., filed a concurring opinion, in which HARLAN, J., joined, post, p. 54. BRENNAN, J., filed an opinion concurring in the result, in which WHITE and MARSHALL JJ., joined, post, p. 56. DOUGLAS, J., filed a dissenting opinion, post, p. 58.