Impaired Driving (Marijuana)

Following a  roadside stop, police can demand an oral fluid sampleA mixture of saliva and other materials found in the mouth if they suspect you are driving under the influence of a drug. Section 320.14 (1) of the Criminal Code states that it is against the law to operate a vehicle if impaired by alcohol or a drug or by a combination of both. A Department of Justice (DoJ) document (Frequently Asked Questions - Drug-Impaired Driving Laws) states that it is a criminal offence to be at or over a prohibited blood drug concentration for certain impairing drugs, including THCThe psychoactive component of cannabis and cocaine. THC levels are measured by using oral fluid drug screeners.

When it comes to cannabis, there are two prohibited levels for THC. 

• Between two and five nanogramOne billionth of a gram.s (ng) of THC per milliliter (ml) of blood within two hours of driving; and
• Over five nanograms of THC per ml of blood within two hours of driving.

If you were consuming cannabis edibles, keep in mind they don't trigger an immediate high such as cannabis products that are smoked. Edibles are slow-release and can take two hours before the high is felt, though they will show up in oral fluid tests in the same way.

If testing shows that you had between two and five nanograms of THC per millilitre of blood, the lower-tier THC offence is prosecuted by summary convictionUsed for lesser offences and carries a maximum fine of $1,000. There is no mandatory minimum fine for this lower tier.

If five nanograms or more of THC is detected, the charge is a hybrid offenceAn offence the Crown can proceed with summarily or by indictment.. That means the Crown can proceed by indictment in more serious cases or by summary conviction in less serious cases.

Under s.320.19 of the Criminal Code, the higher-tier impaired-driving offences carry mandatory minimum penalties. For a first offence, the minimum penalty is a $1,000 fine. For a second offence, the minimum is 30 days in jail. For a third or later offence, the minimum is 120 days in jail.

The maximum penalty for having five nanograms or more of THC in your blood while driving is two years less a day on summary conviction and 10 years if the Crown proceeds by indictment.

Failing or refusing, without a reasonable excuse, to comply with a lawful demand is an offence under s. 320.15(1) of the Criminal Code. For a first conviction, s. 320.19(4) prescribes a mandatory minimum fine of $2,000. The offence is hybrid, and s. 320.19(1) sets maximum penalties of 10 years by indictment or, on summary conviction, a $5,000 fine, imprisonment for two years less a day, or both. For a second offence, the minimum is 30 days’ imprisonment; for each subsequent offence, it is 120 days.

Under s.320.22 of the Code, the court must consider aggravating factorsAny information or evidence that may result in a heavier sentence when sentencing. These can include whether you:

• caused bodily harm to, or the death of, more than one person
• were racing another driver on a street or public place
• had a passenger under 16 with you
• were being paid to operate the vehicle
• had a blood alcohol concentration at or above 120 mg per 100 mL of blood
• were operating a large motor vehicle; or
• were not allowed under federal or provincial law to operate the vehicle.

Police must tell you about your rights after arrest, including the right to speak with a lawyer. RCMP guidance on impaired-driving investigations says that right can be exercised before testing is done at a police station. Roadside tests and evaluations are usually done before speaking with a lawyer.

In addition to the penalties for cannabis use by drivers set out in the Code, provinces and territories can hand out licence suspensions and financial penalties to those convicted of driving while under the influence of marijuana. For example, in Ontario novice drivers (Cannabis and driving) are not allowed to have any cannabis in their bodies if they are 21 or under, have a G1, G2, M1 or M2 licence, or if they are driving a vehicle that requires an A-F driver’s licence or Commercial Vehicle Operator’s Registration.

In Alberta, novice drivers (Immediate Roadside Sanctions Program of IRS ZERO: Novice) in the class 7 Learner’s licence category and class 5 Graduated Driver Licensing drivers must have a zero blood alcohol/drug level when driving. Penalties for offenders include an immediate 30-day driver’s licence suspension, a seven-day vehicle seizure and a $200 fine.

Most provinces and territories have laws similar to Ontario or Alberta, with licence suspensions and attendance at educational programs part of the penalty.

If impaired operation causes bodily harm or death, see the main Impaired Driving page. The aggravated penalties use s. 320.2 and s. 320.21 and are not unique to marijuana.