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BC marihuana user on vacation

Marihuana and driving in British Columbia

You can now lawfully enjoy marihuana while you visit Washington State and a consequence of the legislative change is that more and more British Columbians are driving south to enjoy a pot-filled vacation. Already there are marihuana festivals, parties and all sorts of events planned to entice cannabis tourists. It seems Washington State will see the benefits in increased tourism.

Of course because marihuana is still the subject of criminal law in Canada, you can’t bring any marihuana back to Canada. But what happens if you smoke marihuana and then drive in BC? What is the status of the law when it comes to cannabis and driving in BC?

Currently, officers may ticket marihuana-using drivers under the Motor Vehicle Act, s.144 (1)(a) or (b) and issue an immediate roadside prohibition under s.215.  Under the Criminal Code officers can charge drivers under the same provisions as they would a drunk driver, s. 253(1)(a).

Studies show THC from marihuana has a negative impact on driving skills, though different than alcohol.  Drivers may experience diminished psychomotor skills, attention span, including tracking-tasks, it reduces accuracy, and impairs cognitive function, like risk-assessment, decision making and planning.

Despite its prevalence and its negative impact, there are relatively few studies or reported judicial decisions relating to driving under the influence of marihuana.

Perhaps pot smokers are too relaxed to drive? Maybe it’s just because there’s a great deal of uncertainty surrounding this area of the law. Of course, one of the reasons that there are so few studies is because study subjects would need to smoke up. In other words, it’s difficult to study the effects of a prohibited substance because you generally aren’t allowed to possess it or use it in the first place.

Officers investigating drugged-driving offences use drug recognition experts who rely on evidence procured by the senses (bloodshot eyes, odor) and the results field sobriety tests, which are a series of subjective coordination and evaluation tests. As a result, it’s very difficult to demonstrate that a person is impaired in their ability to drive as a result of marihuana. Simply put, those detained for further investigation often pass even the subjective sobriety tests.

As of yet, there’s no “pot-alyzer” to detect THC levels and no threshold indicating that the driver is too high to drive, like the blood-alcohol concentration of .08 in the Criminal Code.

In other words, the law is vague.

Are you impaired in your ability to drive because of the recent use of cannabis? If so, don’t drive because you’d be committing a criminal offence. Still, as of now, there is no fixed level of TCH that creates a per se offence in British Columbia.