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Cannabis and impaired driving

Getting behind the wheel while impaired by drugs is not only dangerous, it's against the law. It doesn’t matter which substance you’re impaired by; impaired driving is still impaired driving. 

Studies have shown that, among younger drivers, driving after using cannabis is more prevalent than driving after drinking alcohol.

More young people report getting into a car with a driver who has recently used cannabis, as opposed to driving after using it themselves. (Canadian Centre for Substance Use and Addiction (CCSA) 2017).

After alcohol, cannabis is the most commonly-detected substance among drivers who died in vehicle crashes. (CCSA 2017)

Cannabis significantly affects crucial functions for operating a motor vehicle:

  • It impairs depth perception, concentration and attention span, making it difficult to be aware on the road.
  • It slows your reaction time and decreases muscle strength and hand steadiness. This inhibits your ability to respond to hazards, and makes you a hazard to others.

Drug-impaired driving is a Criminal Code offence in Canada (Criminal Code Se. 253a)

  • The code applies to all motor vehicles including snowmobiles, ATVs, motorcycles, boats and airplanes.
  • It doesn't matter if the vehicle is being operated on a public roadway or on private property –– both are dangerous and illegal.
  • Federal legislation has created a new drug impaired driving offences with specified blood-drug concentration limits for THC (the psychoactive compound in cannabis). Penalties include a maximum $1,000 fine for motorists found to have two nanograms per millilitre but less than five ng/ml of THC in their system. In cases when a driver has either more than five ng/ml of THC or a combination of 2.5 ng/ml and 50 mg/100 ml or more of alcohol, a first offence would be a minimum $1,000 fine, a second offence would result in a mandatory 30 days of imprisonment, and a third offence would land a motorist with a mandatory 120 days of imprisonment.

In preparation for cannabis legalization, police officers received specialized training in drug detection: