Pubdate: Fri, 14 Apr 2017
Source: Ottawa Citizen (CN ON)
Copyright: 2017 Postmedia Network Inc.
Author: Tom Spears
Page: A3


Testing to see who's too stoned to drive is a cumbersome system that
results in few convictions, says a law professor who has studied
cannabis impairment.

The federal Liberals have tabled legislation to legalize marijuana
while having severe penalties for drug-impaired driving. But Robert
Solomon of Western University says that enforcement of laws involving
pot and driving can be difficult.

First, forget about a handy roadside breath test like the test for
alcohol, he advises.

"There is some preliminary research indicating that a breath test can
be developed for cannabis. It's slow, expensive and not yet reliable,"
he said. "So we're a long way from a breath test for cannabis ...
(despite) some promoters out there who have been touting miraculous,
easy, cheap" breath tests.

That leaves three options, Solomon says: Today's version: A police
officer pulls over a driver and begins with a field sobriety test.
These are simple tasks. For instance: Can you walk in a straight line?
If you fail that, you're given a breath test, and if this shows that
alcohol isn't your problem, then police can take you away for "drug
recognition evaluation," or DRE.

This is a 12-part test. The first 11 steps deal with physiological
aspects - pulse, temperature, signs of needle marks, and some signs of

The final step, if a driver seems impaired, is to demand a sample of
urine, blood or saliva.

"The difficulty is that the request for a sample is at the end of the
process," he said. Cannabis dissipates from the blood quickly, and he
says it may take up to two hours to reach the point where a driver
actually provides the sample.

"The longer the delay, the more likely that the person is not going to
test positive."

He says it also costs $17,000 to train one officer in this process.
The officer has to compile a long list of points in the

"And the simple fact is that our courts haven't been very receptive to
the DRE evidence.

"We have more people on our roads who are positive for drugs than for
alcohol. And yet drug-impaired driving charges constitute two to three
per cent of all impaired driving charges." Option two: Australia and
some countries in Western Europe allow police to demand a saliva
sample from anyone they pull over, just as they can ask for your
licence and ownership papers.

In some jurisdictions, any THC (the active chemical in marijuana) is

It's still a two-step press, Solomon said: A roadside test, followed
by a second test by a more sophisticated machine, which can be saliva,
blood or urine. Option three: Again there's a roadside saliva test and
a second test at the police station or hospital, but this time the
driver is charged only if the THC content is above a certain level.
That makes this system like our alcohol law: A little drug is all
right, but anything over a certain line counts as impairment, no
matter how a person is acting.

In California, one law firm that specializes in marijuana impairment
cases says police rely on three main "field sobriety tests" to begin
the evaluation process. They ask a driver to walk in a straight line;
they look for "involuntary jerking of the eye" and they ask the driver
to stand on one foot.
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MAP posted-by: Matt