Charles Katz used a public telephone booth in Los Angeles to transmit illegal gambling wagers by telephone to clients in Boston and Miami. Without physically entering the booth, FBI agents attached an electronic listening and recording device to the outside of the booth and recorded Katz’s side of the conversations. The government introduced the recordings at trial, and Katz was convicted under a federal statute prohibiting transmission of wagering information by wire. Katz argued that the recordings were obtained in violation of the Fourth Amendment because they were made without a warrant.
Does the Fourth Amendment prohibit the government from warrantlessly recording a person’s conversations in a public telephone booth when the person seeks to preserve the conversation as private?
The Fourth Amendment protects people, not places. A search occurs when the government violates a person’s reasonable expectation of privacy, even without a physical trespass into a constitutionally protected area.
Yes. The FBI’s electronic surveillance of Katz’s phone booth conversations was a search and seizure within the meaning of the Fourth Amendment, and because it was conducted without prior judicial authorization and outside any recognized exception, it violated the Fourth Amendment.
The Court rejected the earlier property-based approach that turned on physical penetration of a protected space. Although the phone booth was in a public place, Katz entered it, shut the door, and was entitled to assume that his words would not be broadcast to the world; what he sought to keep private was constitutionally protected. The agents’ electronic monitoring captured the contents of his conversations, which implicated the core privacy interests the Fourth Amendment safeguards. Because the surveillance was conducted without a warrant and was not justified by exigent circumstances, the evidence was inadmissible.
Justice Black dissented, arguing that the Fourth Amendment protects only tangible things such as persons, houses, papers, and effects, and does not extend to the recording of spoken words in the absence of a physical search or seizure of those enumerated items.
Katz is a foundational Fourth Amendment decision because it shifted the doctrine from a trespass/property model to a privacy-based model. Justice Harlan’s concurrence supplied the influential 'reasonable expectation of privacy' formulation that became the dominant test in search cases. The decision effectively displaced the approach of Olmstead v. United States, 277 U.S. 438 (1928), and was later limited in part by United States v. White, 401 U.S. 745 (1971), Smith v. Maryland, 442 U.S. 735 (1979), and United States v. Jones, 565 U.S. 400 (2012), which revived trespass analysis while preserving Katz’s privacy framework.
Olmstead v. United States, 277 U.S. 438 (1928) |
Verified |
United States v. White, 401 U.S. 745 (1971) |
Abstain |
Smith v. Maryland, 442 U.S. 735 (1979) |
Abstain |
United States v. Jones, 565 U.S. 400 (2012) |
Abstain |
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