Overview
Often a drinking and driving charge can be defended by showing that police or other authorities violated your rights under the Canadian Charter of Rights and Freedoms. A drinking and driving investigation where breath tests are conducted can engage the following constitutional rights.

If one or more of these rights is breached before the breath tests are completed, it may be possible to exclude the test results and secure your acquittal on a charge of over 80. Similarly, evidence of impairment may be excluded and a charge of impaired driving dismissed if a breach occurs before the observations of impairment are made. A charge of refuse sample may be dismissed if a Charter violation precedes the refusal.

Right not to be arbitrarily detained
When police pull you over a detention occurs. Under Section 9 of the Charter, police can lawfully stop you only if they have “articulable cause.” That is, there must be objectively discernible facts that enable police to form a reasonable suspicion you are committing a crime. Without such facts, detention is arbitrary. A mere hunch based on intuition is not enough – even if it proves accurate.

However, the right can be limited. In Ontario, for example, the Highway Traffic Act allows police to stop you at random to check your driver’s licence and insurance, sobriety and the mechanical fitness of your vehicle. Although there is no “articulable cause” for random stops, the Supreme Court of Canada has held that they are justified because they help detect impaired drivers.

How might this help to defend a drinking and driving charge? Police cannot stop you at random if they have a “hunch” you are concealing drugs or weapons or involved in other crime. If they initiate a random stop for reasons unrelated to your sobriety or motor vehicle and end up charging you with a drinking and driving offence after they smell alcohol on your breath, it may be possible to exclude the evidence and get the charge dismissed.

Right to be secure against unreasonable search or seizure
When you blow into a breath instrument, police “seize” a sample of your breath. For the seizure of breath samples at the police station to be lawful, police need to have reasonable grounds to believe you are committing the offence of Over 80 or Impaired Driving when they demand you undergo breath tests. A “fail” result on a roadside screening device normally furnishes such grounds, as do indicia of driver impairment.

How might this help to defend a drinking and driving charge? The “fail” must be registered on a properly functioning roadside screening device. If there is no evidence that the device is in proper working order, the fail cannot give rise to a reasonable belief that you are Over 80. If police arrested you only because you failed the roadside screening device test, the subsequent breath-test results may be excluded.

Similarly, if police arrest you for Impaired Driving, the observations of impairment prior to your arrest must be sufficient to create a reasonable belief you are impaired. Speeding, weaving from lane to lane, smell of alcohol on your breath, and red, glassy eyes likely justify an arrest. But if police arrest you for Impaired Driving only because you’re speeding and your breath smells of alcohol, the arrest may be unlawful and the results of subsequent breath tests may be excluded.

Right to counsel
Once you’re arrested for a drinking and driving offence and before a breath test, you have the right to speak to a lawyer without delay and to be informed of that right. If police infringe these rights, the results of any subsequent breath tests may be excluded, resulting in your acquittal on the charge of Over 80.

Language difficulties: You must be told of your right to counsel meaningfully and comprehensibly. If you are not a native English speaker, police may have to use an interpreter and if you want to consult a lawyer they may have to put you in touch with one who speaks your language. For an example, see R. v. R.D. in cases.

Holding off requirement: Once you tell police you want to talk to a lawyer, police must hold off from eliciting further evidence until you have spoken to one. For example, they cannot subject you to breath tests or question you about your drinking.

Counsel of choice: In addition, police must make reasonable efforts to facilitate your contact with the lawyer of your choice. If your lawyer does not answer the phone, police may have to leave a message and wait for a response. They may be violating your rights if they compel you to settle for advice from state-funded duty counsel if your lawyer cannot be reached right away.

Even if your trial prospects look bleak initially, authorities may breach your Charter rights in the course of bringing your case to trial, as explained below, enabling you to avoid conviction.

Right to make full answer and defence

The Charter entitles everyone facing a criminal charge to obtain from the Crown all information reasonably capable of affecting their defence. This information, required to make full answer and defence, is referred to as “disclosure.” In a drinking and driving case, disclosure includes the notes police record during the investigation and a copy of the videotape or DVD, if any, showing your breath tests. You also have a right to know what civilian witnesses have told police. In a refuse sample case, you may be entitled to examine the mouthpiece for defects. The loss or destruction of these materials may bar the Crown from continuing your prosecution.

Right to trial within a reasonable time

Under the Charter, everyone has the right to be tried within a reasonable time. In a case tried in the lower court (in Ontario, Court of Justice), the delay from the charge to the actual or anticipated end of the trial – less any delay for which you’re responsible – must not exceed 18 months. For cases tried in superior court, a 30-month ceiling applies. The Crown can justify longer delay only by demonstrating exceptional circumstances. Unless it does so, your charge will be stayed.

Where delay is below these limits, you can establish a breach of your right only by showing that you were consistently proactive in trying to expedite the proceedings and that the case took “markedly” longer than reasonably necessary. The Supreme Court of Canada in a recent case held that such cases will be rare.