The Ministry of Public Safety announced a three-year study into cannabis and driving, three months before marijuana is legalized. File photo

In a haze: Cannabis impairment still unclear for drivers in B.C.

Feds launch three-year study with mere months to go before legalization across Canada

In less than three months marijuana will officially be legalized across Canada and Oct. 17 will be a big day for law enforcement, as research is still underway to determine how the practical implications of the new legislation will be rolled out.

Earlier this month the federal Ministry of Public Safety announced it is launching a three-year study into the effects of cannabis on drivers. The nearly million dollar study will place drivers aged 19 to 45 in simulated driving scenarios to see how different levels of THC – the psychoactive ingredient in cannabis – affects their driving ability.

Why the government decided to look into this now and not earlier remains a mystery (the Ministry has not replied to multiple requests for comment). What is even more unclear is how drivers’ sobriety will be determined in the fall.

Scott MacDonald is a health sciences professor at the University of Victoria who recently retired as assistant director at the Canadian Institute of Substance Use Research (CISUR).

ALSO READ: B.C. ‘will be ready’ for marijuana legalization

He explained that law enforcement officers will use an oral test to check the THC level in a driver’s saliva. A blood test would later be administered to find the exact levels of THC in the individual’s system.

Bill C-46 is aiming to change the criminal code regarding impaired driving, and sets two threshold levels for THC in the bloodstream, with the first at two nanograms, the next at five ng. Theoretically, the higher the levels, the higher the impairment – and potentially the higher the fine.

The problem, MacDonald said, is how THC is metabolized by the body.

“THC binds to the fat cells of the body, so they’re kind of released slowly over time,” he said. “You’re not really high, but it can go back into your blood and remain in your system for quite some time.”

He noted that this is very different from alcohol, which is eliminated from the body at a very constant rate.

Heavy marijuana users – those who smoke every day – can build up quite a tolerance. They can hold THC in their systems up to five days after they smoked, reaching levels of at least two nanograms in an oral test even though, at that point, they would not present any symptoms of intoxication.

“What happens when people have cannabis is their THC levels rise very rapidly, and could [increase] to over 100 nanograms in the first 15 minutes,” MacDonald said. “Then, they decline very rapidly by 90 per cent in the first hour, then kind of level off. It’s when the THC has levelled off that it’s very difficult to pick a cut off point that would be accurate.”

MacDonald believes the numbers to be used to test if someone is high, are too low.

“This is a step above zero-tolerance; they’re not impaired-based laws like we have with alcohol.”

Marijuana edibles bring an even greater challenge, he said, since ingested cannabis not only takes longer to kick in – averaging about an hour – but also creates a completely different chemical reaction.

“It goes directly to stomach and liver and when it’s metabolized, it creates a new compound called hydroxy-THC,” MacDonald said. “It’s more potent than THC itself, but no one’s been able to accurately measure hydroxy-THC for an impairment level.”

ALSO READ: Marijuana growing rules aim to protect B.C. farmland

Law enforcement officers will received an approved screening device for oral tests soon, though at this point they don’t know which brand it will be, or when they will receive them.

Sgt. Shannon Perkins works with the traffic section of the Victoria Police Department. She said any such device will only be a tool to go along with their standard field sobriety test (SFST), an impairment check that requires the driver to walk heel-to-toe in a straight line then turn, during which the officer observes their eyes.

In response to MacDonald’s concerns over potential problems with low THC thresholds, Perkins said the specific numbers aren’t the point.

“We need to not get so hung up on levels or the presence of drugs,” Perkins said. “The device leads us to levels, which goes into a larger part of an entire investigation.”

She warned, however, that regardless of how low an individual’s levels may be, different people will react differently to drugs and should simply not drive if they’ve had cannabis.

“If it’s still in their system, how do we know it won’t affect their driving?” she said. “We’d love to tell the public how much they can have, but because we can’t provide that, they need to take responsibility … if the user doesn’t bear responsibility, should society?”

The B.C. Association of Chiefs of Police have instructed police departments to have 30 per cent of their front line officers trained in SFST by October in anticipation of higher instances impaired driving.

“It’s a state of change,” Perkins said. “Police agencies don’t have all the answers yet. There will be case law arguments and changes, and that’s how it goes.”

nicole.crescenzi@vicnews.com

Like us on Facebook and follow us on Twitter
and Instagram

 

Driving high on marijuana will still be illegal when pot becomes legalized, but the impairment enforcement rules still need fine tuning. iStock photo

Just Posted

Nominations wanted for Langley moms in need

The Mama Coach launched the 2nd annual Christmas for Mamas Giveback campaign.

VIDEO: Man killed in shooting at Abbotsford bank

Police believe incident on Thursday night to be targeted

Langley Township council hopefuls take part in Q&A

A Voter’s Guide to key election questions.

Vaudeville keeps senior actors young, active

The Vaudevillians ready to storm the stage with ‘As Time Goes By’

Online fundraiser to cover funeral costs of motorcyclist killed in collision

Larry Nizio, 37, died after crash with pickup truck Oct. 12 in Abbotsford

Singer k.d. lang receives Alberta’s highest honour

Celebrated singer-songwriter k.d. lang received the Alberta Order of Excellence in Edmonton

Trial set for man charged with decades-old murder of Monica Jack

Garry Handlen accused of killing Merritt girl; also charged with Abbotsford murder

Bernardo-like sexual deviancy poorly understood, expert says

What exactly causes such deviance is not known but some evidence exists of physical brain damage to the front part of the brain

Disney on Ice returns to Vancouver with Moana in starring role

Eight shows at Pacific Coliseum in late November

B.C. high school teacher faces sexual assault charges

A Mt. Boucherie teacher has been charged with child luring, sexual exploitation and sexual assault.

Fashion Fridays: You can never have enough shoes

Kim XO, lets you know the best online shopping tips during Fashion Fridays on the Black Press Media Network

Former B.C. cop sentenced to jail ‘in the community’ after caught in Creep Catchers sting

Dario Devic pleaded guilty after getting caught up in Surrey Creep Catcher sting in Whalley in 2016

5 races to watch in B.C.’s municipal elections this Saturday

This year’s election results across more than 160 cities in B.C. will start pouring in after polls close Saturday at 8 p.m.

Annual pace of inflation slows to 2.2 per cent in September: Statistics Canada

Statistics Canada said Friday the consumer price index in September was up 2.2 per cent from a year ago compared with a year-over-year increase of 2.8 per cent in August

Most Read