Saliva tests for cannabis won't provide an accurate depiction of impaired driving

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      Changes to impaired-driving laws in preparation for cannabis legalization are not only proving flawed but are threatening the charter rights of all drivers on the road, even those who have never consumed pot.

      Since amendments to Bill C-46 passed in June—adding more cannabis-specific laws to the Impaired Driving Act—Canadian drivers have mainly focused on what tools police will use to detect drug intoxication.

      The Justice Department announced that it plans to introduce a roadside saliva test to detect cannabis-impaired driving. With a few swipes of an oral-fluid collection tip over a driver’s cheeks and tongue, police officers will be able to instantly identify traces of tetrahydrocannabinol (THC)—the primary psychoactive compound found in cannabis—ingested within the previous six hours.

      Last month, Justice Minister Jody Wilson-Raybould announced a 30-day notice of a ministerial order to approve the German-made Dräger DrugTest 5000, a portable substance-detection device that looks like a small Keurig coffee machine for spit. Instead of a coffee, this machine will brew up a nice hot cup of reasonable grounds for an officer to proceed to a blood test or expert drug evaluation.

      Drivers could then face a criminal conviction if found with as little as two nanograms of THC in their system, according to the newly set limits.

      Sarah Leamon, a Vancouver lawyer specializing in cannabis law, said these devices are on par with a flawed approach to cannabis legalization. “It’s a big problem to treat cannabis impairment the same way under the criminal law that we treat alcohol impairment,” she told the Georgia Straight by phone.

      “The bottom line is that all of these devices don’t have any reflection on the level of impairment at all when it comes to the subject of the test,” Leamon said, adding that, unlike alcohol, the way cannabis affects each consumer is highly individualistic.

      Under the Criminal Code, 80 milligrams of alcohol per 100 millilitres of blood, or 0.08 percent, is considered legal intoxication. Leamon said that, barring a few variables like weight, this is accurate for most alcohol consumers but the same approach cannot be applied when it comes to cannabinoids.

      “THC is stored in fat cells long after the effects have worn off. It is not metabolized through the body in a consistent rate and there really is no formula for us to determine how it moves through every human body,” she said.

      Depending on factors like a strain’s cannabinoid concentration and consumption method, impairment levels vary drastically from person to person. Cannabinoids can be detectable in frequent consumers, including those who rely on cannabis to treat medical conditions, weeks after their last use.

      Leamon said drivers also need to be aware of amendments that effectively change the way alcohol will be policed at the roadside. Currently, for example, if an officer has reasonable grounds to suspect a driver has consumed alcohol, they can make a breathalyzer demand. Bill C-46 will eliminate that.

      “Now it’s going to be arbitrary mandatory breath-testing at the roadside. For alcohol, the officer won’t have to have an odour or an admission…and the only prerequisite is that the officer has a breathalyzer in their possession,” she said.

      With drug saliva tests, however, the officer must have a reasonable suspicion before proceeding.

      Leamon said she expects this to be one of many constitutional challenges come October, including those stemming from a lack of information linking cannabis to impairment—an area to which Ottawa has allocated $1 million for future research.

      Despite the recent changes, Leamon said she believes that enforcing criminal penalties is not necessarily the most effective way to create safe-driving practices.

      “Instead of passing all of these laws that are potentially flawed and contrary to the charter, what they [the government] should be doing is investing in a strong public-education campaign. People need to understand how to properly use cannabis in a responsible and safe manner in relation to their motor vehicles,” she said.

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