What does impairment of driving ability mean?
Impaired driving ability refers to a decrease in driver judgment. The concept is therefore not tantamount to drunkenness and doesn’t need to be a significant impairment of driving ability.
Is impaired driving only related to alcohol or drugs?
The degree of impairment is not quantified but is based on all the facts of the case. The driver may therefore be found guilty even if his or her conduct was not significantly affected by the use of drugs or alcohol.
Therefore, the person does not have to be completely intoxicated for the evidence to be conclusive. All it will take is for his behaviour to deviate from his normal behaviour. More specifically, proof beyond a reasonable doubt that the degree of impairment is significant enough to affect the driver’s judgment or conduct.
Degrees of tolerance according to individuals
Since the degree of tolerance differs from person to person, an individual might consume a large amount of alcohol and not have any symptoms of impairment, while another might be more impaired after consuming very little. In other words, a person with low alcohol tolerance can still have symptoms of impaired ability without exceeding the legal limit of 80 mg.
Moreover, since the subject of the offence is a weakened driving ability, erratic conduct is not necessary to prove the offence. However, such driving is often caused by the driver being impaired by alcohol or drugs. Therefore, if it is shown that the accused’s driving was faultless, it may serve to raise a reasonable doubt in the judge’s mind in order to obtain an acquittal.
Defining the cause of impaired driving
Driving must be impaired by alcohol and/or drug use. Therefore, a person cannot be charged with impaired driving solely because of factors such as fatigue, stress or disability. The evidence must demonstrate that a substance has been consumed (and this substance must be specified). However, fatigue combined with alcohol or drug use can, for example, influence driving ability and still cause impairment.
When a person falls asleep at the wheel after consuming very little alcohol and causes an accident, it is necessary to consider whether the driving was affected solely by sleep, alcohol or a combination of the two. Alcohol consumption must be linked to impairment of ability, otherwise it is not an offence under the Criminal Code. Similarly, if an accident occurs, there must be a convincing relationship between alcohol or drug use and the accident.
In other words, an accident will not automatically be related to the fact that the individual had consumed alcohol. Moreover, it has been established in case law that poor judgment on the part of a driver is not systematically linked to a weakening of his or her driving ability.
When should I call a lawyer?
In conclusion, before entering a guilty plea to this charge, it is recommended to consult a lawyer to ensure that the prosecution is in a position to prove your guilt beyond a reasonable doubt.
Contact our firm for more information or to benefit from the expertise of our lawyers.
Reference: Criminal Code 2018; Impaired Driving in Canada: the Charter Cases, second edition, by Justice Joseph F. Kenkel; Capacités affaiblies : principes et application, 3rd edition, by Karl-Emmanuel Harrison