United States v. Karo
Headline: Electronic tracking device monitoring limited: Court reverses appeals court and holds installing a beeper with seller’s consent is not a Fourth Amendment search, but warrant required to monitor it inside private homes.
Holding:
- Requires a warrant to monitor beepers when signals reveal location inside private homes.
- Makes law enforcement seek warrants before electronic tracking that invades home privacy.
- Limits use of warrantless beeper monitoring in storage lockers and private residences.
Summary
Background
The dispute arose after DEA agents, with a government informant’s help, arranged for a radio transmitter ("beeper") to be placed in a five-gallon can of ether that was sold to several buyers. Agents tracked the can as it moved through houses, storage lockers, and vehicles and used beeper information to get a search warrant for a Taos house. The district court suppressed the evidence because a prior court order authorizing installation was found invalid; the court of appeals required a warrant to install and monitor beepers in homes and lockers. The United States appealed to the Supreme Court.
Reasoning
The Court addressed two questions: whether placing a beeper with the seller’s consent becomes a search or seizure when the can is later transferred to an unaware buyer, and whether monitoring a beeper that reveals information unavailable to visual observation is subject to the Fourth Amendment. The Court held that the mere installation did not violate the Fourth Amendment because the placement was consented to by the original owner and the substituted can was government property. But monitoring that disclosed the can’s presence inside a private residence was a search and required the protections of a warrant. The Court distinguished Knotts, where beeper use revealed only movements visible to the public.
Real world impact
The decision means police cannot freely monitor electronic tracking devices to learn what is happening inside homes without a warrant. Law enforcement should seek warrants before monitoring beepers when signals could reveal location inside private residences. Whether evidence is excluded depends on whether the warrant affidavit contained sufficient untainted facts; the Court found enough untainted information to reverse the suppression in this case.
Dissents or concurrances
Justice O'Connor, joined by Justice Rehnquist, argued for a narrower test focused on a person’s interest in the container; Justice Stevens, joined by Justices Brennan and Marshall, would treat the beeper attachment as a seizure and affirm suppression.
Opinions in this case:
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