Katz v. United States · ¶10

The question remaining for decision, then, is whether the search and seizure conducted in this case complied with constitutional standards. In that regard, the Government’s position is that its agents acted in an entirely defensible manner: They did not begin their electronic surveillance until investigation of the petitioner’s activities had established a strong probability that he was using the telephone in question to transmit gambling information to persons in other States, in violation of federal law. Moreover, the surveillance was limited, both in scope and in duration, to the specific purpose of establishing the contents of the petitioner’s unlawful telephonic communications. The agents confined their surveillance to the brief periods during which he used the telephone booth, and they took great care to overhear only the conversations of the petitioner himself.

U. S. Reports, bound volume
U. S. Reports, volume 389, at 347 (Library of Congress) · transcription: Caselaw Access Project
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