HOT TOPIC FOR THE LAW

Whenever police want to learn what's going on inside someone's home, they
should have to get a search warrant; even when they don't plan to enter the
house, but just want to look inside with an infrared camera.

That's the principle which is at stake in a case the Supreme Court of
Canada is now considering, on whether a Windsor-area man's privacy was
violated by police who used an infrared camera to look for the telltale
excess heat of a marijuana grow-op.

Walter Tessling isn't the most sympathetic victim of state intrusion -- he
was indeed growing marijuana -- but the highest court in Ontario found that
police went too far before they got a judge's permission. They'd already
been tipped off by informants, but to get a warrant to search Mr.
Tessling's property physically, they used a heat-sensing camera to look for
the energy given off by the powerful lights and warm water a large-scale
growing operation needs. The trouble is, they didn't get a warrant to
"look" inside the house with that camera.

In other words, they already suspected Mr. Tessling of breaking the law,
but they didn't feel their informants' tips were solid enough to get the
search warrant they wanted. So they used surveillance technology to
investigate what was going on behind his walls in order to bolster their
case for being allowed to physically enter the property to conduct a
detailed search.

Currently, infrared cameras can't "see" people through walls, but the
technology is still evolving and it's not unreasonable to think it will be
a possibility in the not-too-distant future. That's why this case is
important not just for people who might be under suspicion of growing
marijuana, but for everyone who believes what they do in the privacy of
their home is nobody's business but their own.

Even now, when used up close infrared cameras can identify internal
hot-spots that could tell police what occupants of a home are doing: if
they've got a fire crackling, say, or if they've drawn a hot bath on a cold
day. Some people might not mind the police knowing that sort of thing about
them, but that doesn't make it OK for the police to invade their privacy
without a properly obtained search warrant.

Grow-ops are still illegal in Canada, many are fire hazards and most are
fuelled by stolen electricity, so the police are right to try to shut them
down. As we have written before, however, this problem likely would go away
if the federal government legalized marijuana, but as it won't do that,
police must continue to pursue the grow-ops that exist.

If the Supreme Court rules in favour of the police in the Tessling case, it
should be with the caveat that evidence of unusual amounts of heat
emanating from a house must not be the only basis for issuing a search
warrant for a more intrusive search. There should also be other
corroborating evidence to justify the physical search. Also, the court
should anticipate the evolution in technology and make it clear that using
infrared cameras that allow police to see actual people inside a home must
not be used without a warrant being obtained in advance.

Better still, the court could bar any attempts to intrude on Canadians'
privacy without a warrant.