The Vinson Court ruled in Kovacs v. Cooper (1949) that the city of Trenton, New Jersey, could prohibit the use of sound amplifiers or loudspeakers on vehicles. The challenge to the ordinance occurred after a city police officer found a sound truck that was broadcasting music. The owner of the truck, Charles Kovacs, was found guilty of violating the ordinance. He contended that the ordinance violated his First Amendment free-expression rights. The U.S. Supreme Court disagreed, reasoning that city officials could restrict such devices. “There is no restriction upon the communication of ideas or discussion of the issues by the human voice, by newspapers, by pamphlets, by dodgers,” the Court wrote. “We think that the need for reasonable protection in the homes or business houses from the distracting noises of vehicles equipped with such sound amplifying devices justifies the ordinance.”

However, the Vinson Court ruled that city officials may not pick and choose which persons can use loudspeakers. In Saia v. New York (1948), the Court invalidated a Lockport, New York, ordinance that required individuals to obtain a permit before being able to use a loudspeaker on public streets. The ordinance gave the mayor unbridled discretion to determine which individuals could have a permit. The mayor denied a request by a Jehovah’s Witness minister. “When a city allows an official to ban them in his uncontrolled discretion, it sanctions a device for suppression of free communication of ideas,” the Court wrote.