Katz v. United States

Katz v. United States, 389 U.S. 347 (1967), is a landmark decision of the United States Supreme Court.

FBI agents attached an eavesdropping device to the outside of a public telephone booth used by Charles Katz, who was convicted of transmitting gambling information. The government argued that the Fourth Amendment did not apply because the phone booth was not a physical ‘constitutionally protected area.’

Significance

Justice Stewart’s 7-1 opinion overturned Katz’s conviction and established the ‘reasonable expectation of privacy’ test. The Fourth Amendment protects people, not places. Justice Harlan’s concurrence articulated the two-part test: (1) the person must have exhibited an actual (subjective) expectation of privacy, and (2) the expectation must be one that society is prepared to recognize as reasonable. Katz replaced the old trespass-based approach from Olmstead v. United States (1928) and remains the foundational test for Fourth Amendment protection.

Category

US Federal Case Law