Pot joins alcohol on the roads

More B.C. drivers using pot
1 Apr 2015, 24 Hours Vancouver
Research finds more drivers are under the influence of cannabis on B.C. roads
More B.C. drivers are behind the wheel while under the influence of cannabis. Anarticle in the April issue of the BC Medical Journal points to a recently-released 2012 study that found cannabis in 5.4% of drivers, compared to 4.6% in 2008.

Even in 2008, an article in the journal stated, “The rate of cannabis use in B.C. drivers is particularly high.”

Research of injured drivers from the BC Trauma Centre found “12.6% of (injured) drivers tested positive for cannabis metabolites, and 7.3% were positive for THC, indicating recent use.” They also found, “Cannabis was more common in males and in drivers younger than 30 years of age.” A limousine driver was at Vancouver City Hall Tuesday morning, appealing a decision to have his permit revoked after a police officer found cannabis in the limo and determined hewas too impaired to operate the vehicle. The driver, Mohammed Samrat Showkat, was pulled over after officers alleged the vehicle was swerving, speeding and changing lanes without signaling. The officer called as a witness testified that she saw and smelled cannabis in the limo and the drivers eyes had an “overall pink hue ... distinctive to marijuana.”

She said she then performed several tests to determine his level of intoxication. These included having him walk in a straight line while counting his steps.

“While he was counting, he became very confused,” she said, adding that he walked with his arms raised, “that appeared to be for balance.” She also tested his ability to track an object with his eyes and how long he could stand on one foot —“he put his foot down after count one,” she said.

The driver’s appeal was denied Tuesday afternoon.

Vancouver Police Chief Const. Jim Chu spoke out Tuesday about a November arrest, also involving an allegedly impaired driver, whichwas caught on video.

“Marijuana smoke billowing from the car made the cause of that impairment obvious,” he said. “In order to make the arrest, force became necessary when the person refused to exit the vehicle, which is understandable since he allegedly knew what would be found in his car if he did.”

The video, available on YouTube, has prompted criticism of the officer smashing the car window. Chu said the officer was “criticized for doing his job.”

Chuck Varabioff, director of the BC Pain Society — an illegal dispensary that sells marijuana for medical use — said there are some types of marijuana that are safe to use while driving.

“The only marijuana that would be completely safe to use while driving would be a CBD (Cannabidiol) strain without THC,” he said.

Since people metabolize drugs at more diverse rates than alcohol, there are no specified generic amounts for how much marijuana is safe to use before getting behind the wheel. According to the BC Medical Journal, “Cannabis slows reaction times, causes weaving, creates difficulty maintaining a constant speed, and predisposes to distraction,” and “Evidence suggests that acute cannabis use approximately doubles the risk of crashing.”

Doctors are recommending governments work together to establish better screening tools and improve legislation around drug-impaired drivers.
Related topic:
Pot-smoking drivers prompt warning from Vancouver ER doctor

1 comment:

  1. Cannabis does cause some impairment, however studies have shown that consumers tend to overestimate this impairment, and that they compensate for it with added caution. Alcohol tends to do the opposite, consumers perceive their impairment to be less that what it actually is and often become overconfident, aggressive, and careless. [Robbe and O'Hanlon. 1993; Robbe. 1995]

    In 2015 the U.S. government completed the largest case controlled study to date regarding DUI of cannabis and crash risk [Compton and Berning. 2015]. It involved over 9,000 cases and controls spanning a 20-month period. It found that cannabis use while driving is not associated with increased crash risk once adjusted for confounding variables such as age, race, gender, and the presence of other drugs, including alcohol. Further, they found that cannabis did not add to the crash risk for drivers under the influence of alcohol. They did find that alcohol significantly increased crash risk, double risk at 0.05% BrAC, 23 times risk at 0.20% BrAC.

    That said, at some point one could be high enough to significantly increase crash risk, something roughly the equivalent of 0.08% BAC, and DUI laws should reflect that. However it is rare for anyone that high to want to actually drive a car, whereas it is commonplace for someone very drunk to attempt to drive.


    --Compton and Berning. DOT HS 812 117. Drug and Alcohol Crash Risk. U.S. Department of Transportation - National Highway Traffic Safety Administration. 2015.
    --Robbe and O'Hanlon. DOT HS 808 078. Marijuana and actual driving performance. U.S. Department of Transportation - National Highway Traffic Safety Administration. 1993.
    --Robbe H. Marijuana’s effects on actual driving performance. HHMRC Road Research Unit, University of Adelaide. 1995.

    Colorado legalized recreational cannabis in Dec 2012 (Jan 2014 for retail sales) and did not see a statistically significant change in yearly traffic fatalities:

    2012: 474 (Population: 5.19 million, 0.0091%)
    2013: 481 (Population: 5.27 million, 0.0091%)
    2014: 479 (Population: 5.36 million, 0.0089%)
    [SOURCE: Colorado DOT & "As Reported" to NHTSA by FARS]