HIGH-TECH SNOOPING

The Fourth Amendment's ban on unreasonable searches was crafted by the
Constitution's framers to create a barrier against government
intrusions on Americans' privacy. An important case argued recently in
the Supreme Court tests the continued vitality of that protection in
the face of high-tech snooping devices that make it increasingly
possible to monitor activities inside a person's home without any
physical intrusion.

The case concerns a thermal imaging device used by federal officers in
Oregon to confirm their suspicion that a man was illegally growing
marijuana. The device detected the distinctive heat pattern generated
by high-intensity lamps used to accelerate the growth of the plants.
At issue is whether the officers violated the Fourth Amendment by
failing to obtain a warrant before aiming the thermal imager at the
house.

The government argues that no privacy right attaches to the "waste
heat" the device measures and that the images the device generates are
too murky to reveal detailed or "intimate" information. But the
information the government obtains need not be intimate to constitute
a violation of privacy. The important point is that the government was
not deploying the device merely to measure heat loss, but to obtain
information about activities inside a private home.

Under court precedents, someone who conducts business in front of open
window shades has forfeited any expectation of privacy. But it would
be an extraordinary leap for the justices to conclude, as did the
lower court, that Americans waive their right to privacy in their
homes by failing to take precautions to block the escape of "waste"
heat.

Some 34 years ago, the court recognized the privacy threat posed by
technological advances in surveillance tools by requiring police to
obtain a search warrant before placing a listening device on the
outside of a phone booth where someone was conducting a bookmaking
business. Today a new generation of snooping tools is expanding the
government's ability to stealthily obtain confidential information.
Whether the Fourth Amendment's core privacy values survive these
advances is now up to the justices.