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Kyllo v. United States

Supreme Court of the United States · 2001 · Criminal Procedure

Criminal ProcedureFourth Amendmentthermal imaginghometechnologysearchwarranthome

Facts

Federal agents suspected Danny Kyllo was growing marijuana inside his home, in part because indoor growing commonly uses high-intensity lamps. From public streets at about 3:20 a.m., agents used an Agema Thermovision 210 thermal imager to scan Kyllo's triplex and detected that parts of Kyllo's home were relatively hotter than the rest of the house and warmer than neighboring units. Relying on tips, utility bills, and the thermal imaging results, a magistrate judge issued a warrant, and agents found an indoor marijuana-growing operation with more than 100 plants. Kyllo was indicted and unsuccessfully sought suppression of the evidence.

Issue

Does the government's use of a thermal-imaging device from a public street to detect relative amounts of heat within a private home constitute a search within the meaning of the Fourth Amendment? If so, was that surveillance presumptively unreasonable without a warrant?

Rule

Obtaining by sense-enhancing technology any information regarding the interior of the home that could not otherwise have been obtained without physical intrusion into a constitutionally protected area constitutes a search, at least where the technology in question is not in general public use. Where the government uses such a device to explore details of the home that would previously have been unknowable without physical intrusion, the surveillance is a search and is presumptively unreasonable without a warrant.

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

Officers in Boise suspect Priya Desai is running an illegal grow operation inside her duplex. Without a warrant, they stand on a public sidewalk and use a specialized infrared scanner, not commonly owned by the public, to determine which rooms inside the duplex are producing unusual heat patterns.

Under the majority's rule, is the officers' use of the scanner a Fourth Amendment search?

Explanation. Yes. The majority adopted a bright-line rule for the home: obtaining by sense-enhancing technology information regarding the interior of the home that otherwise could not have been obtained without physical intrusion is a search, at least when the technology is not in general public use. It does not matter that officers stood in a lawful public vantage point, nor does the rule turn on whether the information revealed 'intimate details' in some narrow sense.