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United States v. Karo

Supreme Court of the United States · 1984 · Criminal Procedure

Criminal ProcedureFourth AmendmentSearch and SeizureElectronic Surveillancebeeperelectronic trackingprivate residencesearch

Facts

DEA agents, with the consent of informant Muehlenweg, substituted a can of ether containing a beeper for one of ten cans ordered by respondents and tracked the can as it moved among houses, storage facilities, and eventually to a Taos residence. Agents used the beeper to determine at several points that the ether was inside private places, including the Taos house, and that information was included in the affidavit for a search warrant. The warrant was executed at the Taos residence, where cocaine and laboratory equipment were seized. Respondents moved to suppress, arguing that installation and monitoring of the beeper were unlawful.

Issue

Whether installation of a beeper in a container of chemicals with the original owner's consent, before delivery to an unsuspecting buyer, constitutes a search or seizure under the Fourth Amendment, and whether warrantless monitoring of the beeper violates the Fourth Amendment when it reveals information about the presence of the container inside a private residence that could not have been obtained by visual surveillance.

Rule

Placement of a beeper in a container with the consent of the then-owner does not itself infringe any Fourth Amendment interest and is neither a search nor a seizure, because it conveys no information and does not meaningfully interfere with possessory interests. But monitoring a beeper is a Fourth Amendment search when it reveals information about the interior of a private residence that could not have been obtained through observation from outside the curtilage; absent an applicable exception, such monitoring requires a warrant. If unlawfully obtained beeper information is included in a warrant affidavit, the warrant remains valid if the remaining untainted facts independently establish probable cause.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

In Phoenix, agents suspected Omar Vega of buying chemicals for a drug lab. With the consent of Desert Mesa Supply, which still owned the shipment, agents placed a radio beeper inside one sealed drum before the drum was delivered to Omar; the device was not monitored until after delivery.

Did the placement of the beeper itself violate Omar's Fourth Amendment rights?

Explanation. The majority held that placing a beeper in a container with the consent of the then-owner does not itself infringe the later recipient's Fourth Amendment interests. It is not a search because the unmonitored beeper conveys no information, and not a seizure because it does not meaningfully interfere with possessory interests. The rule does not turn on reasonable suspicion.