Court Says No to Home Snooping

The police cannot use heat detectors and other such high-tech devices to look inside a person’s home, the Supreme Court ruled Monday.

In a surprisingly strong defense of the right to privacy, the court threw out drug evidence against an Oregon man who was growing marijuana in his house and ruled that law enforcement agents violated his rights by using a thermal imager on a public street to spot his hothouse.

Justice Antonin Scalia, a conservative who usually supports the government in the war on drugs, said that spying inside a home is a different matter. He spoke for the 5-4 majority, which included an unusual coalition of conservatives and liberals.

“The 4th Amendment draws a firm line at the entrance to the house,” he said. “That line, we think, must be not only firm but also bright. . . . Where, as here, the government uses a device that is not in general public use, 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.”

The ruling appears to put a significant limit on the government’s use of new technologies that can pick up sounds or images inside a home.

“This is an important victory for the 4th Amendment because it says again the home is a protected area,” said University of Iowa law professor James Tomkovicz, who filed a friend-of-the-court brief for the American Civil Liberties Union. “I think [the justices] were worried about what comes next, the technology that would allow the government to stay out but detect what is going on inside the home.”

The justices have struggled over the years to decide what constitutes a search.

They have upheld the use of drug-sniffing dogs and officers using binoculars to look in a yard. In such instances, they have said officers on a public street are free to use their senses, including their eyes, to peer into a private area.

In a more controversial decision, the justices upheld the use of low-flying aircraft and helicopters that spotted marijuana growing in homes and yards. Again, the court reasoned that officers were just using their eyesight.

But Scalia said there is nothing natural or obvious about using a thermal imager to detect heat from a home.

In their defense, government lawyers argued that they were not looking inside the house but had picked up the heat waves that were coming out of it. Moreover, they were standing at a distance and not intruding into the owner’s personal space, they said.

The court’s majority refused to accept those distinctions. Allowing sophisticated searching devices as long as they were kept distant from the home “would leave the homeowner at the mercy of advancing technology--including imaging technology that could discern all human activity in the home,” Scalia said.

His opinion in Kyllo vs. U.S., 99-8508, was joined by Justices David H. Souter, Clarence Thomas, Ruth Bader Ginsburg and Stephen G. Breyer. Conservatives Scalia and Thomas frequently find themselves aligned against the more liberal Souter, Ginsburg and Breyer, but search-and-seizure cases in recent years have scrambled the typical ideological divisions.

Despite its broad language, the principle set in Monday’s ruling is limited in its application. It dealt only with a private residence, not a car or a work site.

In the past, the justices have given police far more leeway to stop cars and search them for evidence of a crime. They have said that motorists give up much of their right to privacy when they travel on the public streets.

Monday’s ruling is also narrowed by its application only to an initial search for evidence. If police already have clear evidence of a crime inside a home, such as testimony that a homeowner is growing marijuana, officers can obtain a search warrant to enter the house legally.

Under the ruling, authorities technically could employ thermal imaging with a search warrant, but as a practical matter the warrant would render such surveillance techniques unnecessary.

In the case, federal agents used the thermal images to convince a magistrate that the homeowner, Danny Lee Kyllo, was growing marijuana.

The thermal imager works like a video camera, except that it shows white heat spots. The scan of Kyllo’s triplex in Florence, Ore., showed unusual heat coming from the roof of the garage and one side wall.

When agents raided his home, they found more than 100 marijuana plants growing under bright lights.

Kyllo challenged the use of the drug evidence, but eventually pleaded guilty.

The U.S. 9th Circuit Court based in San Francisco upheld the search because the thermal imager picked up heat waves on the outside of the house and did not look inside.

In dissent, Justice John Paul Stevens called the ruling unwise and suggested it may someday limit the government’s ability to detect a bomber or a terrorist.

“Heat waves, like aromas that are generated in a kitchen, or in a laboratory or opium den, enter the public domain if and when they leave the building,” he said. New devices “might detect the odor of deadly bacteria or chemicals for making a new type of high explosive,” he said, adding that the ruling could restrict law enforcement’s capacity to use such devices. His dissent was joined by Chief Justice William H. Rehnquist and Justices Sandra Day O’Connor and Anthony M. Kennedy.

A spokeswoman for the Los Angeles Police Department said officers used dogs to sniff for drugs but did not use thermal imagers.

Thermal imagers are used by police departments across the country for several purposes that will not be affected by the ruling.

If nothing else, Monday’s ruling shows again that the court in general, and the justices in particular, are none too consistent on matters involving unreasonable searches and seizures.

The decision itself marked the third major ruling this year in which the justices have rejected drug searches and put new limits on the war on drugs.