DRIVING AND POT

Here's what cops want you to remember: James McIlwrick was high on
marijuana and prescription drugs the morning he slammed a pickup truck
into another vehicle two years ago, killing Tammy Engelking and Henry
Yao.

Here's what they'd rather you forget: your chances of being caught
driving under the influence of pot are slim to none.

Unless you get into a serious accident - or confess to a police
officer in a moment of stoned candour - you're probably going to get
away with it.

And there are probably a lot more stoned drivers on the highways than
anyone cares to admit. McIlwrick's case was an odd one: having caused
the crash outside Sherwood Park that killed Engelking and Yao, he
freely admitted to emergency medical staff and police at the scene
he'd smoked a joint earlier in the day.

He also copped to consuming the drugs Ativan, Zyprexia and Zithromax,
which contributed to his drowsy state.

"It's a rare case," said Crown prosecutor Greg Marchant. "I've been
doing this work for five years, and I can only remember one
drug-impairment case involving (marijuana)."

Can you test a driver for marijuana impairment? Not without his
permission - or a court order. Because alcohol distributes evenly
throughout the body, a breath test actually gives a very near estimate
of how much booze made it to the brain.

Police officers can also force you to take a roadside breath test on
suspicion, or as part of a random checkstop.

Cannabis is complicated. The active ingredient in weed, for instance,
collects in fatty tissues. Breath samples are useless. Even blood
samples aren't completely reliable - and they're not much good from a
legal point of view.

"Police have no legal right to compel a blood test, even if they
suspect impairment," said local criminal lawyer Robert Shaigec. "A
blood sample is considered intrusive under the law. A breath sample
isn't."

Let's settle something right now: marijuana does impair your ability
to drive safely. I know I'm going to get a lot of e-mails from
lifetime weed smokers claiming the stuff makes them better drivers.

Not true. Wise up.

"It impairs visual function, your ability to follow moving objects,"
said Doug Beirness, senior research associate with the Canadian Centre
on Substance Abuse.

"Drivers under the influence of marijuana tend to show slower reaction
times, an inability to respond adequately to unexpected events.
They're easily startled, and they have trouble deciding what to do in
an emergency situation."

Marijuana has one effect it doesn't share with alcohol: people high on
weed tend to be very aware of their impaired state. So while drunks
drive recklessly, a driver high on cannabis will more often drive
slightly below the speed limit and leave larger gaps between his car
and other traffic.

But he's still impaired - when something goes wrong, studies show the
stoned driver is at a higher risk of being responsible for a
collision. His diminished reflexes make him an unsafe driver, even if
he's driving under the posted limit. And when cannabis is combined
with booze, the likelihood of an accident increases again.

But because a lot of people think driving stoned is safe, a lot of
people are doing it. A recent study found roughly 2% of Ontarians
reported driving under the influence of cannabis in the previous year.
Among regular users, that percentage jumped to 23%.

There's no legal limit for cannabis impairment in the Criminal Code,
because there's no practical way to test for it. A British company has
a patent on a device that tests saliva for marijuana's active
ingredient, and Australian cops are using it. But it's not cleared for
Canadian courts.

In the meantime, police have something called the Drug Recognition
Expertise protocol. Crafted by the RCMP, its a checklist of signs and
symptoms used by cops to detect impairment by all sorts of drugs, weed
included. There are five DRE-trained officers in Alberta now, and
another 24 should be trained by the end of November.

"But again, we can't compel a driver to submit to a DRE test," said
RCMP Cpl. Evan Graham, national DRE co-ordinator. "There was a bill
before Parliament that would have given us that power, but it died
with the election."

"Basically, police are left with their own observations as evidence.
Was the driver slurring his speech, was he weaving in the lane?" said
Beirness.

"But in the absence of medical evidence of impairment, that's probably
not going to be enough for a conviction. Any lawyer could get the
charge tossed in about two minutes."