Researchers out of the University of British Columbia say Canada’s cannabis impairment driving penalties may be too strict when it comes to low levels of THC. In a new study, recently published in the journal Addiction, UBC researchers looked at how alcohol and other illegal drugs impacted car collisions, but found no connection with low levels of THC, the main psychoactive ingredient in cannabis, and car crashes.
Current Canadian laws on drug impairment penalize drivers caught with blood THC levels of between two and five nanograms per millilitre with a maximum $1000 fine. And if drivers are found to have five nanograms or higher, they are slapped with a minimum $1000 fine while also facing up to 10 years in prison time for a first offence.
Lead author Dr. Jeffrey Brubacher, associate professor in the department of emergency medicine at UBC, looked at 3,000 blood samples of people that were injured when driving between 2010 and 2016. He determined that blood THC levels at five nanograms, or below, does not appear to be associated with an increased risk of crashing.
And Brubacher recommends Canada’s laws should be changed to not penalize someone with those trace amounts of THC.
“I am leaning in that direction right now based on this study and the concerns we have raised about habitual users having low levels. A medical marijuana user, for example, would never be allowed to drive.”
– Dr. Jeffrey Brubacher, UBC researcher told Postmedia News
Brubacher said in the initial minutes a cannabis user smokes a joint, THC levels spike to around 100 nanograms per millilitre. But this drops to two nanograms or lower in roughly four hours, he said.
But for habitual pot smokers, the psychoactive ingredient THC accumulates in the users body and can be found in the body even days after they smoke, he adds.
– Dr. Jeffrey Brubacher, University of British Columbia
Alcohol and other drugs pose higher risk
Factors such as this add to the complexity of enforcing driving laws and cannabis use. It’s not a cut and dry issue for lawmakers and police, especially compared to alcohol where there is an easy way test and determine if someone is impaired.
In fact, according to the study, alcohol was found to have the highest association with causing car accidents as drivers showing a blood-alcohol content above the legal 0.08 limit are six times more likely to crash compared to non-drinkers.
And with illicit drugs such as cocaine, heroin and amphetamines the increased risk for a crash rose to 82 per cent. Even antidepressants were found to increase the risk by 45 per cent, according to the impairment study. These findings from the study further suggest that more sophisticated testing is needed so that cannabis impairment laws can be adjusted and more adequate roadside tests can be administered.
Police say effective roadside testing still needed
Indeed, one of the biggest challenges with cannabis legalization has been how police can accurately determine if someone is driving under the influence. Because marijuana can stay in a person’s system for days and many different variables can impact how long it will stay in your blood, there will likely be numerous false positives.
And police have already stated this is a difficult situation to manage. Due to the ambiguity of the testing and without an accurate way to prove someone was actually impaired and under the influence of cannabis when driving, lawyers could have a field day defending impaired driving charges.
The police are still waiting for a more accurate testing device that would go beyond testing for the presence of marijuana in a driver’s saliva to providing a precise amount, police said.
But until then marijuana users, especially chronic ones, could be at risk of being found under the influence of cannabis even if they aren’t. Ultimately, it’s likely going to come down to the discretion of the officer to assess whether someone is impaired or not.