News / Vancouver

Driving high on B.C.'s highways: Can cops catch cannabis DUIs?

As legalization looms, experts, entrepreneurs and officers ask if province is road-safety ready

Opthalight Digital Solutions co-founder Ehsan Daneshi wears an eye-testing device developed by the Vancouver firm he co-founded with ophthalmologist Dr. Amir Vejdani, left.

Jennifer Gauthier / Metro

Opthalight Digital Solutions co-founder Ehsan Daneshi wears an eye-testing device developed by the Vancouver firm he co-founded with ophthalmologist Dr. Amir Vejdani, left.

As Canada readies to legalize pot this summer, experts including an ex-traffic cop warn we're still stumped about stopping stoned drivers from hitting B.C.'s streets.

"I've stopped lots of people who have been under the influence of marijuana," recalls retired West Vancouver traffic enforcement officer Cpl. Grant Gottgetreu, who earned the nickname "Darth Radar" for his 2,000-plus speeding impounds over his 22-year career. "You had to get really good at making observations.

"Unless a person gets pulled over and there's an overwhelming smell of burned marijuana from the car … there's still no instrument out there to test like there is for alcohol yet."

And although federal bill C-46 sets the maximum level of pot's psychoactive chemical, THC, allowed in drivers' blood at two nanograms per millilitre, it's currently stalled in the Senate after being approved by the MPs in October. The delay has pushed back legalization's start beyond the original July 2 date.

But will that buy enough time to solve the street-stoned motorist conundrum?

"The medical and scientific community still have to come up with a number that corresponds with impairment," Gottgetreu added. Like alcohol, pot will have to be out of drivers' reach and is banned outright for new drivers. But without a limit or an easy way to measure it, busting marijuana-addled motorists is a problem that's vexing many provincial public safety ministers, including B.C.'s.

Mike Farnworth told reporters on Feb. 5 he's waiting to see what happens in Ottawa.

"It's one of the areas I've said where we have real concerns about when the equipment to test that's being used will be ready," he said, "and the training that's going to be required."

But some Canadians' lax attitudes to being lit behind the gear shift, according to opinion polls, has researchers like UBC Medicine clinical assistant professor John Staples worried.

He compared fatal accident stats in the U.S. (where a much-larger population, and more public data, better reveals trends) between three dates over 25 years and found a 12 per cent spike on April 20 after 4:20 p.m. — when yearly marijuana "4/20" events begin.

And under-21 fared worse, seeing a 38 per cent rise compared to the control days.

"The numbers are quite surprising," he said. "We're the first to admit that while 4/20 is strongly associate with cannabis, it's quite likely that lots of people celebrating it are also drinking alcohol and using other drugs. Certainly there's some evidence to suggest that driving risks are magnified when cannabis and alcohol are combined."

A 2012 B.C. report found that 7.4 per cent of randomly chosen drivers had one or more "potentially impairing substance" other than booze detected in their saliva — 44 per cent of which was THC.

Bill C-46, if passed, would create new offenses for driving over the allowed "blood drug concentration," still to be decided by Cabinet, and would allow "peace officers who suspect a driver has a drug in their body to demand that the driver provide a sample of a bodily substance for analysis by drug screening equipment" approved by Ottawa.

Saliva testing is one promising option, but the most surefire test currently is to test blood, but that is fraught with rights and civil liberties questions.

"It's extremely intrusive," Gottgetreu noted. "And who would collect the blood?"

Another promising solution is an impairment test developed by Vancouver-based medical device firm Opthalight, which uses a head-mounted tool to test how a subject's eyes react to stimulus.

But while co-founder and vice-president Ehsan Daneshi, a Simon Fraser University computational neuroscientist, said he had police DUI testing in mind, the firm decided it was too financially risky without government or other funding.

"Businesswise, it’s risky," he explained. "At the end of the day, maybe we have a couple different companies with different technology, but probably only one will sign a contract with the government — and the other is out of the market.

"If government could actually make a new stream for funding these kinds of technologies that would help. But without those technologies yet? Just legalizing marijuana I’m not sure is the best decision to make at this time."

Another problem is how long THC stays in the body, he added.

"Maybe you used the drug last night or 24 hours ago — you'd have no problem for driving but you’d get a false positive result."

Instead, Daneshi's product has been successfully applied to medical research and optometry uses, although he'd be open to revisiting the DUI testing application if the conditions were right. But he's confident other researchers and entrepreneurs like him are exploring similar solutions — and hopes governments step up.

Staples agreed that technology is important as legalization approaches. "But beyond that downstream effort to catch drivers who are impaired, it's important we think about other policies to prevent impaired driving from occuring in the first place.

"A substantial minority of Canadians believe intoxication with marijuana doesn't affect their driving. That's simply not true. Don't drive high."

After 22 years in traffic enforcement, Gottgetreu isn't sure there will suddenly be "pandemonium" on B.C.'s roads once legalization comes into force. But until there's a reliable roadside test, enforcement will continue to require "good old-fashioned police work." When he started out, there were no handheld alcohol breathalizers, either.

"It's going to be a logistical nightmare for the courts to deal with," Gottgetreu predicted. "You have to convince the judge of the reliability of the evidence … if they're not convinced, they're obviously not going to convict.

"I learned very early on in my career that if I got frustrated with every court decision, I'd have an ulcer by the time I was 40. But it's an interesting time we're heading into now."

Correction (Feb. 21): Gottgetreu impounded roughly 2,200 vehicles for speeding over 22 years; an earlier version of this story misstated that was the number of speeding tickets he issued, which in fact was many times that amount.

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