Road Safety Information

Drug Impaired Driving

Last Updated on October 12, 2021

The effects of psychodynamic drugs such as cannabis, amphetamine, cocaine, and anti-depressants on driving vary by drug. They generally result in slower reaction time, failure to identify danger, poor decision-making, and falling asleep at the wheel. (For more information see: https://druggeddriving.tirf.ca/module/the-effects-of-drugs-on-driving/#tabid/1

Prevalence:

Data from the National Collision Database (NCDB) indicate that in 2019, 3 percent of all road fatalities in Canada involved a driver being under the influence of drugs which was slightly higher than in 2008 (2 percent). Canadian coroner data for 2017 indicate that 44 percent of fatally injured drivers tested positive for drugs compared to 41 percent in 2008.[1]Brown, S., Vanlaar, W., and Robertson, R. (2021). The Alcohol and Drug-Crash Problem in Canada: 2017. Report prepared for the Canadian Council of Motor Transport Administrators. The prevalence of cannabis increased from 18 percent in 2008 to 20 percent of fatally injured drivers in 2017, a 35 percent increase.

Night-time roadside surveys in five jurisdictions in 2017 and 2018 (British Columbia, Manitoba, Ontario, Yukon, and Northwest Territories) determined that 10.2 percent of drivers tested positive for the presence of at least one potentially impairing substance other than alcohol.[2]Beirness, D. J. (2020). A Compilation of Jurisdictional Roadside Surveys Conducted Prior to Cannabis Legalization. Report prepared for Canadian Council of Motor Transport Administrators. The drivers who tested positive for cannabis represented 75 percent of drivers who had drugs present. In a 2012 British Columbia (BC) survey, 7.4 percent of drivers tested positive for one or more drugs, and of these, 44 percent had been using cannabis. In a 2018 BC survey, 8.5 percent of drivers tested positive for one or more drugs an increase of 15 percent compared to 2012.[3]Beirness, D. J. and Beasley, E.E. (2019) Alcohol and Drug Use by Drivers in British Columbia: Findings from the 2018 Roadside Survey, Beirness & Associates, Inc. Of the drivers who tested positive for drugs, 71 percent had cannabis present. In an Ontario roadside survey, drugs were detected in 10.2 percent of drivers in 2014. This climbed to 14.2 percent in 2017, an increase of 39 percent. In 2014, 7.0 percent of drivers tested positive for cannabis which climbed to 10.6 percent in 2017[4]Beirness, D. J. (2018) Alcohol and Drug Use by Drivers in Ontario: Findings from the 2017 Roadside Survey, Beirness & Associates, Inc., an increase of 51 percent.

A survey by the Traffic Injury Research Foundation in 2019 found that 7 percent of drivers admitted to driving within two hours after consuming cannabis, more than double the percentage observed in 2010.[5]Woods-Fry, H., Vanlaar, W., Lyon, C., Brown, S., and Robertson, R. (2019) Road Safety Monitor 2019: Trends in Marijuana Use Among Canadian Drivers, Traffic Injury Research Foundation, November 2019.

Countermeasures:

Changes to the Criminal Code of Canada in 2018 added several new offences regarding driving and cannabis use:

  • driving with Tetrahydrocannabinol (THC) levels over 2 nanograms will result in a charge which on conviction will result in a fine of $1,000,
  • driving with THC at a level over 5 nanograms will result in an impaired driving charge,
  • driving with a level over 2.5 nanograms of THC and 50 mg or more of alcohol will result in an impaired driving charge.

On conviction, the latter two offences are subject to the same penalties as alcohol impaired driving (i.e., fines, licence suspensions, jail).

Further information about cannabis impaired driving laws can be found at:

Police are often on the lookout for both alcohol and drug impaired driving. The 2018 changes to the CCC now allow police officers to demand saliva samples from drivers at the roadside to test for the presence of psychodynamic drugs.

Public awareness programs have been conducted by various governmental and non-governmental agencies regarding the effects of drugs such as THC on driving and the consequences of being convicted of drug impaired driving.

For example:

Drug Impaired Driving FAQs:

How do psychodynamic drugs affect driving abilities?
Psychodynamic drugs such as cannabis, amphetamine, cocaine, anti-depressants can lead to slower reaction times, failures to identify danger, poor decision-making, falling asleep at the wheel, and other driving impairments.
What percentage of fatally injured drivers test positive for psychodynamic drugs?
Coroner data for 2017 indicate that 44 percent of Canadian fatally injured drivers tested positive for drugs compared to 41 percent in 2008. The prevalence of cannabis increased from 18 percent in 2008 to 20 percent in 2016.
What is the prevalence of driving after using drugs in Canada?
According to roadside surveys conducted in five Canadian jurisdictions (British Columbia, Manitoba, Ontario, Yukon, and Northwest Territories) in 2017 and 2018, 10 percent of drivers tested positive for drugs between the hours of 9:00 pm and 3:00 am.
What is the federal law regarding impaired driving in Canada?
Changes to the Criminal Code of Canada in 2018 added several new offences regarding driving and cannabis:

  • driving with Tetrahydrocannabinol (THC) levels over 2 nanograms will result in a charge which on conviction will result in a fine of $1,000,
  • driving with THC at level over 5 nanograms will result in an impaired driving charge,
  • driving with over 2.5 nanograms of THC and 50 mg or more alcohol will result in an impaired driving charge,

On conviction, the latter two offences are subject to the same penalties as alcohol impaired driving (i.e., fines, licence suspensions, jail).

How do the police know if a driver is under the influence of drugs?
Police are on the lookout for both alcohol and drug impaired driving. In addition to administering a standardized field sobriety test and/or a breathalyzer test at the roadside, the 2018 changes to the Criminal Code of Canada now allow police officers to demand a saliva sample from drivers to test for the presence of psychodynamic drugs. If these tests indicate drug use, the driver is arrested, taken to the police station, and required to provide a blood sample and/or will be evaluated by a Drug Recognition Expert to determine impairment.
Back to Road Safety Information

References

References
1 Brown, S., Vanlaar, W., and Robertson, R. (2021). The Alcohol and Drug-Crash Problem in Canada: 2017. Report prepared for the Canadian Council of Motor Transport Administrators.
2 Beirness, D. J. (2020). A Compilation of Jurisdictional Roadside Surveys Conducted Prior to Cannabis Legalization. Report prepared for Canadian Council of Motor Transport Administrators.
3 Beirness, D. J. and Beasley, E.E. (2019) Alcohol and Drug Use by Drivers in British Columbia: Findings from the 2018 Roadside Survey, Beirness & Associates, Inc.
4 Beirness, D. J. (2018) Alcohol and Drug Use by Drivers in Ontario: Findings from the 2017 Roadside Survey, Beirness & Associates, Inc.
5 Woods-Fry, H., Vanlaar, W., Lyon, C., Brown, S., and Robertson, R. (2019) Road Safety Monitor 2019: Trends in Marijuana Use Among Canadian Drivers, Traffic Injury Research Foundation, November 2019.