What is impaired driving/DUI?

In Canada, impaired driving means the operation (driving), care or control of a motor vehicle, vessel or aircraft while your ability to operate is impaired by alcohol or a drug.

Impairment is an issue of fact, which the trial judge must decide on the evidence. The prosecutor must prove the case (the accused does not have to prove they were not impaired). The standard or degree of proof required before a judge will convict is the same as in all criminal cases:. the judge must be convinced "beyond a reasonable doubt" that the charge has been proved.

If the evidence of impairment is so frail as to leave the trial judge with a reasonable doubt as to impairment, the accused must be acquitted. If the evidence of impairment establishes any degree of impairment ranging from slight to great, the offence has been proved.

What evidence of impaired driving must the prosecution prove?

To prove this charge, the prosecutor must call evidence that shows signs of impairment. A breath test is not required to prove impaired driving. The charge is mainly proved through observations of the accused, which are most often given by a police officer. This normally includes evidence of:

• an unusual pattern of driving (bad driving)
• the odor of alcohol coming from the accused
• red glassy, watery or bloodshot eyes and/or dilated pupils
• slurred speech
• flushed complexion
• unsteady on their feet
• difficulty producing documents
• any other evidence showing symptoms of impairment

The prosecution will argue that all of the above symptoms are evidence of impairment.

How can an impaired driving charge be challenged?

While the points listed above may be evidence of impairment, this is not necessarily the case. Evidence that at first appears to support an impaired driving charge may be as consistent with innocence as with guilt, or as consistent with normal but imperfect driving, and not necessarily impairment.

How can you appear impaired but not be impaired?

An unusual pattern of driving may be caused by vehicle (mechanical) defect, road conditions or the driver being momentarily distracted.

The odor of alcohol is consistent with its recent consumption, but is not necessarily indicative of impairment. (Remember, just because a person has been drinking doesn't mean they are impaired.) The odor of alcohol may also be coming from somewhere other than breath (for example, if alcohol was spilled on clothing).

Glassy, watery and bloodshot eyes are consistent with being over-tired, being in a smoky room, or many other causes. They are not necessarily caused by impairment.

Slurred speech may be caused by reasons other than impairment, such as dental or medical problems.

Unsteadiness or lack of balance might be caused by footwear, medical conditions or the condition of the surface the person is walking on.

Difficulty producing documents can be caused by nervousness (some people get nervous when stopped and questioned by police).

The case for the defence.

In addition to challenging the prosecution's case through skilled cross-examination, your defence lawyer may be able to lead evidence of your sobriety. There may be witnesses who will testify that you drank moderately and behaved normally.

If you're charged with impaired driving, here's the bottom line.

Nothing can be taken for granted. If you are charged with impaired driving, all is not lost. An experienced impaired driving lawyer should conduct a detailed examination of the circumstances that led up to the charge.

In addition to challenging the evidence against you, the prosecution's case may have procedural problems that, if challenged, can result in a finding of not guilty.