HEAT DETECTION AND PRIVACY RIGHTS

In the early morning hours of Jan. 16, 1992, an agent of the Oregon
National Guard sat in his car and aimed an Agema Thermovision 210 at Danny
Lee Kyllo's home in Florence, Ore.

The heat-detection device showed that one wall of the home emitted an
unusually high amount of heat.

THE AGENT ALREADY suspected Kyllo of drug-related activities, and utility
records showed a high use of electricity. The ``thermal imaging device''
the agent employed amplified the probability that Kyllo was growing
marijuana in his house.

Based on that information, the agent obtained a search warrant, and sure
enough, the heat detected was emanating from high-intensity lights used to
grow marijuana. Kyllo was arrested.

Kyllo sought to throw out the evidence against him, arguing that the use of
the heat-detection device amounted to an unlawful search. A trial judge
disagreed, but an appeals court ruled the agent should have obtained a
search warrant before using the device. Then the appeals court changed its
mind. Now the case is before the U.S. Supreme Court.

This could be one of many cases in which the court must wrestle with the
problems posed by developing technologies and the rights of citizens to be
generally free of government intrusion under the Fourth Amendment.

Warrantless searches and seizures in a home are ``presumptively
unreasonable.'' But was this a search of a home or merely a measure of heat
radiating from the home?

The Agema Thermovision 210 could detect heat emissions from a variety of
activities that could occur inside a home, from couples embracing to
greenhouse cultivation. But in 1992 the device could not penetrate walls;
rather, the court ruled it measured heat from the walls.

``Whatever its Star Wars capabilities, the thermal imaging device employed
here intruded into nothing,'' the court wrote.

Nevertheless, the high court must be mindful that new technologies can be
far more intrusive.

``I think the average American, myself included, is only beginning to
realize the cost of technology, which as we know is moving forward with
lightning speed, is a loss of personal privacy,'' said American Bar
Association President Martha Barnett last week.

Police and prosecutors often argue that technology simply improves on human
senses without altering any fundamental expectation of privacy.

But technology becomes more intrusive every day.

Police agencies are using alcohol detectors during traffic stops, and
equipment exists to check pupil dilation secretly for signs of drug use.

During the Super Bowl here, security cameras were trained on the faces of
fans as they entered Raymond James Stadium to compare them with digitized
images of known terrorists and other criminals stored in computer banks.

Civil liberties groups believe such intrusions violate at least the spirit
of the Fourth Amendment, and they are not wrong.

We must remain vigilant against the invasions of privacy new technology
affords while not depriving law enforcement of the benefits.

That said, the use of technology in the Kyllo case did not amount to an
illegal search. The thermal imaging device used then did not open up
Kyllo's home to law enforcement.

IT MEASURED HEAT, which is not illegitimate in an investigation of a man
suspected of growing marijuana indoors.

As a precautionary matter, however, it seems to us that police agencies
should, when possible, obtain a search warrant before using intrusive
technologies to preclude any Fourth Amendment questions.