Impaired Driving

What is Impaired driving?

Impaired driving means operating a motor vehicle (such as cars, trucks, ATVs/ORVs, snowmobiles and boats/water vessels) while the ability to do so has been compromised to any degree by consuming alcohol, drugs or a combination of the two.

It is illegal to drive impaired, even by prescription or over-the-counter drugs. If a driver is unsure of whether it is safe to drive while taking medication, he or she should speak to a doctor or pharmacist.


The Effects of Drugs on Driving

The Effects of Drugs on Driving
Drug Class (street name) Signs of Impairment Effects on Driving
Cannabis (weed, pot, ganja)
  • Dilated pupils, red eyes
  • Impaired coordination
  • Slow reflexes
  • Slower speeds
  • Weaving
  • Slow reaction time
  • Poor decision-making in rapidly-changing road conditions
Opioids (heroin, oxy, fentanyl)
  • Droopy eyes
  • Pupils have little/no reaction    to light
  • Sluggish movement
  • Drowsy/sleepy
  • Impaired coordination
  • Poor lane tracking
  • Slower speeds
  • Weaving
  • Slow reaction time
Sedatives (downers, zanies, benzos)
  • Jerky eye movements
  • Impaired movement and balance
  • Drowsy/sleepy
  • Impaired coordination
  • Inattentive
  • Slower speeds
  • Weaving
  • Slow reaction time
Stimulants (crack, coke, crystal)
  • Dilated pupils
  • Body shaking/agitated
  • Talkative/restless
  • Inability to concentrate
  • Poor impulse control
  • Speeding and risk-taking


Drug effects on Driving


Prone to agitation, inability to concentrate, reduced ability to divide attention, poor balance and coordination, increased speeding, increased risk-taking when driving.


Poor motor coordination, slower driving, weaving and delayed reaction time when driving. Drivers who test positive for opioids are up to 8 times more likely to be involved in a traffic collision.


Impaired coordination, sleepiness, inattentiveness, and slower reaction time when driving. Drivers who test positive for sedatives are 2-8 times more likely to be involved in a fatal traffic collision.


Reduced ability to divide attention, distorted time and space management, poor lane tracking, weaving, slower speed, poor focus when driving. Drivers who test positive for cannabis are up to 5 times more likely to be involved in a traffic collision.


Poly Substance Use

The effects of any drug (including multiple drugs) vary from person to person. The effect depends on a range of factors that include a person’s: size, sex/gender, weight, overall health, tolerance and whether it is consumed in combination with other drugs.

Drug combinations (called poly-drug use) may cause one of three reactions: additive, synergistic or antagonistic.

  • Additive Effects occur when drug combinations produce an effect that is like simple addition, such as the equation: 1 + 1 = 2.
  • Synergistic Effects occur when drug combinations produce an effect that is greater than the sum of the effects of the two drugs, such as the equation: 1 + 1 = 3.
  • Antagonistic Effects occur when a drug combination produces an effect that is less than the sum of the effects of the drugs acting alone, such as the equation: 1 + 1 = 1 or 1 + 1 = 0.

These factors make it difficult to predict exactly, and in what way, mixing drugs may affect a person's ability to operate and drive a vehicle safely.


Know the Law

Drivers 21 years and under and/or drivers with G1, G2, M1 or M2 driver’s license are not permitted to have ANY amount of alcohol or drugs in their body while operating a motor vehicle.

First-time offenders face:

  • 3-day immediate license suspension
  • 30-day license suspension, on conviction
  • $60-500 fine, upon conviction
  • $281 license reinstatement fee
  • $1,000 penalty

Young and novice drivers with higher impairment levels still face all of the consequences of fully licensed drivers. For all the comprehensive impaired driving penalties and legislation, please visit Ministry of Transportation: Zero Tolerance Penalties for Young and Novice Drivers.


Police can detect impairment in 3 ways:

  • Standardized Field Sobriety test (SFST)
  • Drug Recognition Expert (DRE)
  • Approve Drug Screening Equipment (ADSE)

If police determine that a driver is impaired, the driver will face penalties immediately. He or she will also face additional consequences upon conviction in court.



Insurers break down driving infractions typically into three types of categories: minor, major, and criminal. Regarding impaired driving:

  1. Impaired driving is NOT a minor or a major conviction. It is a criminal conviction that will have extremely serious and long-lasting consequences to an insurance policy, insurance premiums, and personal finances.
  2. If this is a first impaired conviction, the driver will be non-renewed by the existing insurance company. Depending on the severity of the impaired driving conviction, they will more than likely have their drivers’ license suspended for one year. This means that even after paying the higher insurance premiums, the driver will have to wait an entire year before they can operate a vehicle. Being unable to drive for one year can have significant consequences if the driver requires a vehicle for work/to run errands; or if their family members depend on them to operate a vehicle.
  3. After paying for and completing the “Back on Track” program, and paying all reinstatement/administrative fees: the driver may qualify to get their driver’s license back after the 1-year suspension. Once a driver’s license is reinstated, it will be branded with an “Ignition Interlock Condition” (I) for a minimum period of 1 year from the date of reinstatement. If the driver chooses to drive while their driver’s license is branded with an (I), an Ignition Interlock Device will need to be installed in their vehicle (for a cost of roughly $1,500). The driver will be financially responsible for the installation, maintenance, and registration/monthly fees associated with installing and maintaining the Ignition Interlock Device on their vehicle.
  4. Once the driver begins driving again, they will be subject to different insurance rating rules. They are now considered a high-risk driver and will need to be placed with a high-risk insurance carrier. They will more than likely de dropped down to a “0-star” rating, and their insurance premiums will increase substantially. The premiums could be upwards of $4000-$10,000+ annually depending on their age, type of vehicle, driving record and conviction history.


Tips to Avoid Impaired Driving

There are simple steps you can take to avoid driving while you're impaired by drugs or alcohol:

  • If you choose to use recreational drugs or feel impaired because of prescription medication, have a plan to get home safely:
    • Have a designated driver
    • Use public transit 
    • Call a friend or family member for a ride
    • Call a taxi or rideshare, or
    • Stay overnight.
  • Drug-impaired driving caused by prescribed medications is still a criminal offense. Ask your doctor or pharmacist about side effects related to driving when using prescription medication.
  • Follow the recommended directions on the package of any prescription drugs or over-the-counter medicine, including allergy and cold medications.

Remember that combining drugs and alcohol together can impair your ability to drive more than using either one alone.


For Further Information

Call the Injury Prevention & Substance Use Program: (807) 625-5900

or toll-free 1-888-294-6630

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