The Warren Court ruled in Red Lion Broadcasting Co. v. FCC (1969) that the First Amendment rights of broadcasters should be limited because of the scarcity of broadcast frequencies. This is known as the scarcity rationale. The idea is that if the government does not license and control broadcast frequencies, then the public will be bombarded by different, competing frequencies that will interfere with each other signals.

“Without government control, the medium would be of little use because of the cacophony of competing voices, none of which could be clearly and predictably heard,” the Court wrote. “It would be strange if the First Amendment, aimed at protecting and furthering communications, prevented the Government from making radio communication possible by requiring licenses to broadcast and by limiting the number of licenses so as not to overcrowd the spectrum.”