The case of Heffron v. International Society for Krishna Consciousness (452 U.S. 640 (1981)) gave the basic rules for how time, place and manner restrictions can remain constitutional under the 1st Amendment. The US Supreme Court found that such restrictions are constitutionally permitted as long as they are: Justified without regard to the content of the regulated speech, Serve a compelling government interest, and Leave open ample alternative channels for communication of the information. In this particular case, the Court found that Minnesota could prohibit the distribution of literature at their State Fair except at designated booths. In addition, Minnesota could limit the number of booths, as long as they gave them out on a first-come first-serve basis, regardless of the speaker, viewpoint, or subject matter.