The overbreadth doctrine holds that a regulation that curtails protected speech, even if it also restricts unprotected speech, can be challenged as invalid. The doctrine seeks to strike a balance between competing social costs. On the one hand, the threat of enforcement of an overbroad law deters people from engaging in constitutionally protected speech, inhibiting the free exchange of ideas. On the other hand, invalidating a law that in some of its applications is perfectly constitutional — particularly a law directed at conduct so antisocial that it has been made criminal — has obvious harmful effects.
In order to maintain an appropriate balance, the U.S. Supreme Court has vigorously enforced the requirement that a statute's overbreadth be substantial, not only in an absolute sense, but also relative to the statute's plainly legitimate sweep. Invalidation for overbreadth is "strong medicine" that is not to be "casually employed."
The Supreme Court has also recognized that the assertion of a First Amendment overbreadth claim is not the application of a procedural rule, but a substantive part of the First Amendment. "[O]verbreadth is a function of substantive First Amendment law." As a matter of substantive law, the First Amendment overbreadth doctrine is a constitutional exception to state and federal rules of standing that would otherwise limit a party to an as-applied challenge to a statute. Thus, "[a] state court is not free to avoid a proper facial attack on federal constitutional grounds."
In NAACP v. Alabama, the U.S. Supreme Court said that a law or government regulation “to control or prevent activities constitutionally subject to state regulation may not be achieved by means which sweep unnecessarily broadly and thereby invade the area of protected freedoms.”
- ↑ Virginia v. Hicks, 539 U.S. 113, 119-20 (2003) (full-text).
- ↑ See Board of Trustees of State Univ. of N.Y. v. Fox, 492 U.S. 469, 485 (1989)(full-text); Broadrick v. Oklahoma, 413 U.S. 601, 615 (1973)(full-text).
- ↑ Los Angeles Police Dept. v. United Reporting Publishing Corp., 528 U.S. 32, 39 (1999)(full-text) (quoting New York v. Ferber, 458 U.S. 747, 769 (1982)(full-text)).
- ↑ Sabri v. United States, 541 U.S. 600, 610 (2004)(full-text).
- ↑ New York v. Ferber, 458 U.S. 747, 767 (1982)(full-text).
- ↑ 377 U.S. 288 (1964)(full-text).
- ↑ Id. at 307.