Click on the case titles to link to the full case decision.
Silverman v. US, 365 U.S. 505 (1961)-Officers entered the attached residence next to the petitioner. The officers pushed a listening devise into the petitioner's residence until it contacted the the air ducts. The devise allowed the officers to listen to conversations in the petitioner's residence. The officers violated the petitioner's Fourth Amendment rights because the officers did not obtain a warrant.
Lopez v. US, 373 US 427 (1963)-An undercover officer can use a hidden tape recorder. The recorder was used to obtain the most reliable evidence of the conversation between the officer and the suspect.
Katz v. United States, 389 US 347(1967)-Earlier rulings from the court, particularly the Olmstead case, said that the government can eavesdrop on constitutionally protected areas without a warrant as long as the government does not physically penetrate the areas to accomplish the eavesdrop. The court stated in the Katz case the following: "We conclude that the underpinnings of Olmstead (Olmstead v. United States, 277 U.S. 438) and Goldman (Goldman v. United States, 316 U.S. 129) have been so eroded by our subsequent decisions that the "trespass" doctrine there enunciated can no longer be regarded as controlling. The Government's activities in electronically listening to and recording the petitioner's words violated the privacy upon which he justifiably relied while using the telephone booth and thus constituted a "search and seizure" within the meaning of the Fourth Amendment. The fact that the electronic device employed to achieve that end did not happen to penetrate the wall of the booth can have no constitutional significance. "[389 U.S. 347, 354]
US v. US District Court, 407 U.S. 297 (1972)-The President's Constitutional powers to protect the country do not allow the circumvention of the Fourth Amendment requirement of judicial approval of wiretaps. This applies to domestic security cases.
Smith v. Maryland, 442 US 735 (1979)-The use of a pen register that records only phone numbers does not constitute a search within the meaning of the Fourth Amendment.
United States v. Knotts, 460 U.S. 276 (1983)-The use of a tracking devise on an automobile traveling on public roadways is neither a "search" nor "seizure" and a warrant is not required.
US v. Karo, 468 U.S. 705 (1984)-A tracking devise hid inside an object cannot be used to reveal information about the inside of a residence without a warrant.