Having first arisen in the context of streets and parks, the public forum doctrine should not be extended in a mechanical way to the very different context of public television broadcasting. In the case of streets and parks, the open access and viewpoint neutrality commanded by the doctrine is 'compatible with the intended purpose of the property.' Perry Ed. Assn. v. Perry Local Educators' Assn., 460 U. S. 37, 49 (1983). So too was the requirement of viewpoint neutrality compatible with the university's funding of student publications in Rosenberger v. Rector and Visitors of Univ. of Va., 515 U. S. 819 (1995). In the case of television broadcasting, however, broad rights of access for outside speakers would be antithetical, as a general rule, to the discretion that stations and their editorial staff must exercise to fulfill their journalistic purpose and statutory obligations.
Congress has rejected the argument that 'broadcast facilities should be open on a nonselective basis to all persons wishing to talk about public issues.' Columbia Broadcasting System, Inc. v. Democratic National Committee, 412 U. S. 94, 105 (1973). Instead, television broadcasters enjoy the 'widest journalistic freedom' consistent with their public responsibilities. Id., ...