Can You Refuse a Breathalyzer in Ontario?

Refusing a Breath Sample Is a Criminal Offence

Under section 320.15 of the Criminal Code of Canada, it is a criminal offence to refuse or fail to comply with a demand to provide a breath sample, a blood sample, or to perform physical coordination tests when lawfully demanded by a police officer. The offence applies to both roadside screening demands and station breathalyzer demands.

Parliament created this offence for a specific reason: to eliminate any incentive for drivers to refuse testing. Before the refusal offence existed, a driver could simply refuse to blow and the Crown would be left without breathalyzer evidence. The refusal offence closes that gap by making the act of refusal itself a criminal charge with penalties identical to impaired driving.

The Two Types of Breath Demands

There are two distinct breath demands under the Criminal Code, each with different legal requirements.

Roadside Screening Demand — Section 320.27(1)

A police officer who has an approved screening device (ASD) in their possession can demand a breath sample from any driver who has been lawfully stopped. Since the 2018 amendments introduced by Bill C-46, this is a mandatory alcohol screening power — the officer does not need to suspect that you have been drinking. Any lawfully stopped driver can be required to blow into the ASD.

The ASD produces one of three results: pass, warn, or fail. A “fail” result gives the officer grounds to arrest you and demand a more precise breath test at the station. A “warn” result triggers administrative consequences under Ontario’s Highway Traffic Act but does not, on its own, constitute grounds for a criminal charge.

Evidentiary Breath Demand — Section 320.28(1)

Once you are arrested and taken to the police station, the officer will demand that you provide two breath samples on an approved instrument — a more precise breathalyzer than the roadside ASD. To make this demand, the officer must have reasonable grounds to believe that you have committed an impaired driving offence within the preceding three hours.

Before you provide the station breath samples, you have the right to counsel under section 10(b) of the Charter. You must be informed of this right and given a reasonable opportunity to contact a lawyer. If the police proceed with the breath demand before you have had a chance to speak with counsel, the results may be excluded from evidence.

Penalties for Refusing a Breath Sample

The penalties for a refusal conviction under section 320.15 mirror those for impaired driving and over 80:

Beyond the criminal penalties, a refusal conviction triggers the same collateral consequences as any impaired driving conviction: a criminal record, dramatically increased auto insurance premiums, the requirement to complete Ontario’s Back on Track remedial program, mandatory installation of an ignition interlock device, and inadmissibility to the United States.

What the Crown Must Prove

To convict on a refusal charge under section 320.15, the Crown must prove three elements beyond a reasonable doubt:

1. A demand was made — the officer demanded a breath sample, blood sample, or physical coordination tests.
2. The demand was lawful — the officer had the legal authority to make the demand. For a roadside ASD demand, this means the driver was lawfully stopped and the officer had an ASD available. For an evidentiary demand, this means the officer had reasonable grounds to believe an impaired driving offence had been committed.
3. The accused refused or failed to comply — the accused either outright refused or failed to provide a sufficient sample without a reasonable excuse.

If any of these elements is missing, the charge fails. This is where most refusal defences focus.

Defences to a Refusal Charge

The Demand Was Not Lawful

The most common defence to a refusal charge is that the breath demand was not lawful. If the officer lacked the legal authority to make the demand, there was no obligation to comply, and the refusal is not criminal.

For a roadside ASD demand, the officer must have lawfully stopped the vehicle. While RIDE checkpoints and random traffic stops are generally permissible, a stop motivated by racial profiling or conducted without any legitimate purpose may be unlawful under section 9 of the Charter. Additionally, the officer must actually have an approved screening device available at the time of the demand.

For an evidentiary breath demand at the station, the officer must have had reasonable grounds to believe that the driver committed an impaired driving offence. If the grounds are insufficient — if, for example, the only indicator was a slight smell of alcohol with no other signs of impairment — the demand may be unlawful.

Reasonable Excuse

Section 320.15 provides a defence if the accused had a reasonable excuse for failing to comply. Courts have interpreted this narrowly. Medical conditions that genuinely prevent a person from providing a sufficient breath sample — such as chronic obstructive pulmonary disease, broken ribs from an accident, or a severe panic disorder — may constitute a reasonable excuse if supported by medical evidence.

However, courts have consistently held that the following are not reasonable excuses: fear of the results, desire to speak with a lawyer before deciding whether to blow (the right to counsel does not include the right to refuse the demand), general anxiety, failure to understand the consequences of refusal, and intoxication itself.

Charter Violations

Even where a refusal technically occurred, the evidence may be excluded if the accused’s Charter rights were violated. Common Charter issues in refusal cases include:

• Right to counsel (s. 10(b)) — failure to inform the accused of the right to a lawyer upon arrest, or failure to provide a reasonable opportunity to contact counsel before the evidentiary demand.
• Arbitrary detention (s. 9) — an unlawful stop or detention that led to the breath demand.
• Unreasonable search (s. 8) — in cases involving blood demands, challenges to the manner in which the sample was obtained.

Where a Charter breach is established, the court applies the test under section 24(2) to determine whether admitting the evidence would bring the administration of justice into disrepute. If the evidence is excluded, the Crown’s case may collapse.

Refusal vs. Failure to Provide

Section 320.15 covers both an outright refusal (saying “no” or “I won’t blow”) and a failure to provide a sufficient sample. Failure to provide typically arises when the accused attempts to blow into the instrument but does not produce enough breath for a valid reading — often described as “short blows” or “insufficient samples.”

The qualified technician operating the approved instrument will record whether the accused appeared to be making a genuine effort. If the technician notes that the accused was deliberately providing insufficient samples despite being instructed on proper technique, the Crown will argue that the failure amounted to a refusal. The defence may counter that the accused was genuinely trying but physically unable — particularly if there is a medical condition or injury.

The Strategic Reality

Some people believe that refusing the breathalyzer will make it harder for the Crown to prove impairment. The opposite is true. A refusal charge does not require the Crown to prove your blood alcohol concentration at all — only that you refused a lawful demand. The Crown’s case is often simpler to prove on a refusal charge than on an over 80 charge, because there are no breathalyzer results to challenge.

It is almost always better to comply with the breath demand and challenge the evidence afterward. There are effective defences to over 80 charges — breathalyzer maintenance issues, calibration errors, Charter violations during the testing process, and toxicology evidence challenging the readings. By refusing, you give up access to these defences and face a charge that is at least as serious.

If you have been charged with refusing to provide a breath sample in Ontario, contact our office to discuss your case. The legality of the breath demand, the circumstances of the refusal, and any Charter issues all need to be carefully assessed by experienced counsel.