Lehman (P) was a candidate for public office. He wanted to buy advertising space on buses run by the City of Shaker Heights (D). A private firm under contract with D controlled the advertising space, and a provision of the contract prohibited political advertising. P was refused advertising space and sued D, claiming that public transportation was a public forum protected by the First Amendment. The Supreme Court of Ohio concluded that the constitutionally protected right of free speech with respect to forums for oral speech, or the dissemination of literature on a city's streets, does not extend to commercial or political advertising on rapid transit vehicles. P appealed.