New York Times
June 11, 2001

Court Restricts Heat-Sensor Searches

By David Stout

WASHINGTON -- The Supreme Court today reiterated the right of privacy in the age of technology, ruling in an Oregon drug case that the police cannot use a heat-seeking device to probe the interior of a home without a search warrant.

Use of the heat-sensor without a warrant was equivalent to a "search" under the Fourth Amendment, as opposed to a simple surveillance of the building's exterior, and was therefore improper, the Court held in a 5-4 decision.

The ruling in Kyllo v. United States, No. 99-8508, was notable because it did not follow the general conservative-liberal breakdown among the justices. The majority decision was written by Justice Antonin Scalia, perhaps the most conservative member of the court. It was joined by another conservative, Justice Clarence Thomas, as well as Justices David H. Souter, Ruth Bader Ginsburg and Stephen G. Breyer.

"Where, as here, the government uses a device that is not in general public use, to explore details of the home that would previously been unknowable without physical intrusion, the surveillance is a `search' and is presumptively unreasonable without a warrant," Justice Scalia wrote.

Federal agents did get a warrant to search the home of Danny Lee Kyllo in Florence, Ore., early in 1992, but only after the heat-sensing devices had aroused the agents' suspicions that the unusual heat patterns within the house might be from high-intensity lamps used to grow marijuana — which, in fact, they were.

Mr. Kyllo entered a conditional guilty plea and served a month in jail while challenging the use of the heat sensor. The United States Court of Appeals for the Ninth Circuit, in San Francisco, sided with Mr. Kyllo, then reversed course and issued a new opinion after one of the original members of the three-judge panel retired.

Quoting from earlier rulings involving the Fourth Amendment's provisions against unreasonable searches and seizures, Justice Scalia said that "at the very core" of the amendment "stands the right of a man to retreat into his own home and there be free from governmental intrusion."

"It would be foolish to contend that the degree of privacy secured to citizens by the Fourth Amendment has been entirely unaffected by the advance of technology," Justice Scalia wrote.

The heat device used by the agents "might disclose, for example, at what hour each night the lady of the house takes her daily sauna and bath — a detail that many would consider `intimate,' " the majority held.

Justice John Paul Stevens dissented and was joined by Chief Justice William H. Rehnquist and Justices Sandra Day O'Connor and Anthony M. Kennedy.

The dissenters cited a District Court finding that, in fact, "no intimate details of the home were observed, and there was no intrusion upon the privacy of the individuals."

The dissenters noted, too, that the sensing device used by the agents cannot pick up conversation or reveal human activities.

"Indeed, the ordinary use of the senses might enable a neighbor or passerby to notice the heat emanating from a building, particularly if it is vented, as was the case here," Justice Stevens wrote. "Additionally, any member of the public might notice that one part of a house is warmer than another part or a nearby building if, for example, rainwater evaporates or snow melts at different rates across its surfaces."

Copies of the ruling and dissent may be read on the court's web site:

When the case was argued before the justices on Feb. 20, Mr. Kyllo's lawyer, David Lerner, asserted that it was not fair for citizens to have to anticipate what technology the government would come up with to monitor their activities. That issue seems certain to come up again, long after Mr. Kyllo's less than sensational marijuana case (which was returned to the lower courts to determine how much other evidence investigators have against him) has been decided.

Copyright 2001. New York Times . All rights reserved.

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