Correct answer D. It helped establish a right that is implied rather than direcly stated in the Bill of Rights
Katz was a gambler who used a public phone booth to place bets with his bookies. Turns out, the FBI had placed a wiretap on the phone and was recording his conversations. Katz was arrested and charged with illegal gambling.
The FBI did not have a warrant to tap the phone.
At trial, Katz argued that the recordings were inadmissible because they violated his 4th Amendment right against illegal search and seizure.
The prosecution argued that they weren't specifically searching or seizing anything that belonged to Katz, therefore they didn't need a warrant.
In fact, the tap was on the phone line miles away, the FBI never even touched the phone booth.
The Trial Court found Katz guilty of illegal gambling. Katz appealed.
The Appellate Court upheld the conviction. Katz appealed.
The Appellate Court found that there was no physical intrusion into the phone booth, therefore there was no need for a warrant.
The US Supreme Court reversed.
The US Supreme Court found that if an individual can justifiably expect that his conversation would remain private, their conversation is protected from unreasonable search and seizure by the 4th Amendment.
The Court found that the 4th Amendment is designed to "protect people, not places."
The Court found that the 4th Amendment can still be violated even if there is no physical intrusion of a 'constitutionally protected area'.
Therefore a warrant is required before the government can execute a wiretap, and the warrant must be sufficiently limited in scope and duration.
Basically, this case said that the 4th Amendment is a general right to privacy, not a right to have a specific item or location protected. It doesn't matter where you are, if you feel that you are in private, then you are protected.