UNWARRANTED THERMAL IMAGING'S PROMISING USES STOP AT YOUR DOOR

The technological adaptation seems marvelous, indeed. Especially in Texas,
where the deer and the antelope play, the innovation placed on board
certain automobiles by Cadillac is hardly a toy. It could be a life-saver.

The device, adapted from military applications, is a thermal imager that
allows the driver of a vehicle to "see" down the highway whether there is
something alive that's ready to cross the road or leap into the windshield.
The imager plays off the difference in warmth of animals and the rest of
their surroundings.

Thermal imaging has a number of other uses also not related to warfare.
Nine years ago, federal officers used a thermal imaging device to detect
heat coming from the garage of an Oregon man suspected of growing marijuana
under bright lights.

After detecting the heat, the agents got a search warrant, found 100 pot
plants, arrested the man and convicted him.

The man appealed, and last week the U.S. Supreme Court agreed with him and
his lawyer and issued a ruling that the majority apparently hoped will send
a clear signal to law-enforcement officers that what goes on inside a home
still has some sanctity.

The majority concluded that the Fourth Amendment to the Constitution
requires that government get a warrant to search a home before using a
thermal imaging device, not after.

Actually, according to an analysis of the decision by Jonathan Ringel of
American Lawyer Media, the court's majority did not confine its ruling just
to thermal imaging technology, but to any technology that "is not in
general public use," that can be used "to explore the details of the home
that would previously have been unknowable without physical intrusion." The
court's decision is a sound one, given the very sophisticated technologies
that are being developed and adapted for use in crime fighting. Devices are
routinely advertised in certain magazines and at certain Web sites that, if
deployed, would absolutely deprive anyone even in a concrete bunker of his
or her privacy.

A person's home is his or her castle, and intrusions by strangers deploying
high-tech gear need to be monitored by third parties (the courts) that have
no particular interest in the outcome, other than it be fair and legal and
just.

The ruling doesn't mean this kind of technology can't be used. It simply
means that a judge is going to have to be persuaded by law enforcement that
the intrusion is justified by some amount of evidence obtained in a
different way.

That's a reasonable approach.