How Much Alcohol is Allowed While Driving?
All drivers in Ontario should know how much is too much when it comes to drinking and driving. Mistakes can create dangerous situations, with a lack of coordination and poor reaction time increasing the risk of accidents.
Criminal charges, a hefty fine, license suspension, a criminal record, and even imprisonment can result.
How much alcohol is allowed while driving depends partly on your licence type. For some licence holders, zero tolerance means that charges may result if any alcohol is detected in the driver’s system. For most drivers, however, criminal charges only apply if they exceed the legal blood alcohol concentration level (BAC) or drive impaired.
Let’s look closer at legal alcohol limits and the implications of exceeding these limits…
Legal BAC limits in Ontario
BAC is measured in milligrams of alcohol per 100 millilitres of blood (mg/ml) or as a percentage. The legal BAC limit for driving a vehicle in Ontario depends on your class of licence.
Fully licensed drivers (Class G licence)
- Legal limit: 0.08 BAC
- Warning range: 0.05 to 0.079 BAC
Meeting or exceeding the legal limit while driving on a standard G licence is likely to result in criminal charges. If your breath is measured in the warning range, you will face mandatory administrative penalties at the roadside, issued by a law enforcement officer with no court intervention (more about this below).
Novice drivers (Class G1, G2, M1, M2 licences)
For novice drivers, a zero-tolerance policy means that driving with any alcohol in the blood is an offence and can lead to immediate penalties or criminal charges.
Commercial drivers
The same zero-tolerance policy applies to commercial drivers in Ontario when it comes to drinking and driving. Drivers caught with any alcohol in their blood can face roadside sanctions or criminal penalties, depending on the BAC level.
How is your BAC measured in Ontario?
In Ottawa, law enforcement uses three main methods to check BAC levels:
- Roadside Approved Screening Devices (ASDs), which are portable tests approved under federal law for use at the roadside, such as the Alcotest 7410, Alcotest 6000 or Alco-Sensor IV. These tests usually return a PASS, WARN or FAIL result. FAIL results are often disputed by criminal defence lawyers.
- Station/Mobile-unit Approved Instruments (Evidential Breathalyzers): Drivers who fail an Approved Screening Device test in Ottawa must submit breath samples using a certified evidential machine, usually the Intoxilyzer 8000C, which provides legally admissible BAC readings.
- Blood tests: These tests often provide a more precise method of measuring BAC because a blood sample is lab-analyzed.
What affects your BAC?
A driver’s BAC is affected by multiple factors, which should be taken into account before deciding to drink and drive.
- Body weight: higher body weight usually results in a slower BAC increase, but not always.
- Gender: Females may register higher readings than males after drinking the same amount.
- How much food you’ve eaten: Eating food before or with alcohol may delay the rise in BAC.
- Type/amount of alcohol: Beer, wine, and spirits are all metabolized by the body slightly differently.
- Metabolic rates: Different people have different metabolic rates, meaning that alcohol absorption happens at different speeds.
Understanding how your body reacts to alcohol is essential. If in any doubt, do not drink and drive. The traditional “two drinks” rule is highly unreliable and should never be used nowadays, when roadside sanctions may apply even if you are below the legal limit (WARN range).
Consequences of driving over the alcohol limit
A DUI or impaired driving charge in Ottawa is a serious criminal charge, even for a first DUI offence.
If your BAC measures 0.05–0.079 (WARN range), you will face roadside administrative penalties, including an immediate license suspension of 3, 7 or 30 days depending on your prior record, plus a $250 fine.
If your BAC is over 0.08 or you are deemed to be impaired while operating a vehicle, you will face an immediate roadside license suspension of 90 days, a 7-day vehicle impoundment, and an immediate $550 fine for a first offence.
A conviction from criminal charges will add greatly to the sanctions, including a lengthy licence suspension, a minimum fine of $1,000, and the possibility of jail time, as well as mandatory attendance at education programs and the requirement to fit an ignition interlock device—even for a first offence.
The consequences are unlikely to end there. The criminal record you are left with can have longer-term consequences, potentially affecting employment, housing, insurance, travel, immigration status, and more.
Young or novice drivers who are caught with any alcohol in their system for the first time face a three-day license suspension and fines, while commercial vehicle drivers who breach the zero tolerance laws while operating their vehicle face a three-day license suspension and a fine of $250 for a first offence.
Note that aggravated offences and repeat offenders are treated much more harshly by the justice system.
Can you refuse a breath test in Ottawa?
A breath test refusal at the roadside or a police station in Ottawa can lead to criminal charges and harsher treatment than if you fail a test: a minimum $2,000 fine (first offence), a mandatory one-year driving prohibition, and a criminal record.
Under Criminal Code §320.27(2), police can legally demand a breath sample at any traffic stop without requiring reasonable suspicion. Canada’s implied consent laws mean that drivers automatically agree to comply, and refusal is considered non-compliance.
What if you’re charged?
If you’re charged with a criminal drink-driving offence in Ottawa, saying very little until you’ve consulted with a criminal defence lawyer can prevent severe long-term consequences.
Our office almost never recommends simply accepting the charge and pleading guilty.
A DUI defence lawyer can protect your rights and begin work on a defence strategy, based on the actions of police officers during the stop, procedural errors, Charter Rights, the equipment/testing methods used to measure your BAC or other key evidence from the case.
Contact David Anber’s Law Office Today
David Anber’s Law Office has represented many people charged with DUI offences in Ottawa. To schedule a free consultation and speak with an experienced DUI lawyer, call us toll-free at 1-888-989-3946 or contact us online.