In United States law, a state actor is a person who is acting on behalf of a governmental body, and is therefore subject to regulation under the United States Bill of Rights, including the First, Fifth and Fourteenth Amendments, which prohibit the federal and state governments from violating certain rights and freedoms.
Although at first blush the term would seem to include only persons who are directly employed by the state, the United States Supreme Court has interpreted these amendments and laws passed pursuant to them to cover many persons who have only an indirect relationship with the government. Controversies have arisen, for example, over whether private companies that run towns (the "company-town") and prisons (traditionally a state function) can be held liable as state actors when they violate fundamental civil rights. This question remains unresolved, but the Supreme Court has held private citizens to be liable as state actors when they conspire with government officials to deprive people of their rights. Conversely, in National Collegiate Athletic Association v. Smith, the Supreme Court has found that the National Collegiate Athletic Association is not a state actor, despite its heavy reliance on state-supported educational institutions.
Unlike state actors, private actors are generally not required to afford individuals the constitutional rights mentioned above. In nearly all U.S. states, private shopping center owners can eject protesters from their land for trespassing, and private associations can eject members or deny admission to applicants, with no warning and for no reason. But in a handful of states, notably California, state constitutional protections and certain common law rights have been extended to limit private actors. California allows the peaceful exercise of free speech in private shopping centers (see Pruneyard Shopping Center v. Robins (1980)) and requires certain types of private actors to afford current or potential members a rudimentary version of procedural due process called fair procedure.
There are a number of situations where the United States Supreme Court has recognized the conduct of individuals or private organizations to be “state action,” and therefore subject to provisions of the Constitution such as Equal Protection, Due Process, or the First Amendment. The Supreme Court has held that:
1. Merely opening up a business to the public is not state action, but the performance of a “public function” (a function that has been traditionally and exclusively performed by the state) is state action (Marsh v. Alabama, 326 U.S. 501 (1946));
2. If an individual or organization merely enters into a contract or asserts a contractual right outside of court is it not state action, but if an individual or organization sues to judicially enforce a contractual right it is state action (Shelley v. Kraemer, 334 U.S. 1 (1948));
3. If the government merely acquiesces in the performance of an act by a private individual or organization it is not state action, but if the government coerces, influences, or encourages the performance of the act it is state action (Rendall-Baker v. Kohn, 457 U.S. 830 (1982));
4. If the government merely enters into a contract with an individual or organization for the goods or services then the actions of the private party are not state action, but if the government and the private party enter into a “joint enterprise” or a “symbiotic relationship” with each other it is state action (Burton v. Wilmington Parking Authority, 365 U.S. 715 (1961));
5. If government agencies are simply members of a private organization then the actions of the organization are not state action, but if the government is “pervasively entwined” with the leadership of the private organization then the acts of the organization are state action (Brentwood Academy v. Tennessee Secondary School Athletic Association, 535 U.S. 971 (2002)).