The Canadian law concerning intoxication is not only intensely controversial, but complex. There are four different ways in which intoxication can operate as a "defence" or more accurately prevent proof of the required fault for various criminal offences. The first and simplest is that evidence of intoxication can raise a reasonable doubt as to whether the accused had the intent required for a specific intent offence such as murder or robbery. The issue is the accused’s actual intent, not whether intoxication impaired the accused’s capacity to form the required intent.90The only difficult issues may be whether a particular offence will be classified as a specific intent offence that requires an intent directed at some purpose beyond the immediate action and whether there is an air of reality to justify instructing the jury about this defence.
The second intoxication defence is the Daviault defence of extreme intoxication to general intent offences that do not include an element of an assault or any other interference or threat of interference with of the bodily integrity of another person.91The accused must establish the Daviault defence of extreme intoxication to a general intent crime on a balance of probabilities and with expert evidence. The issue seems to be whether the accused was capable of forming the minimal intent required for general intent offences and not whether the accused actually had that intent, as in the case with the first intoxication defence to specific intent offences. The Daviault defence only exists unimpeded by legislation when the accused is charged with a general intent offence such as mischief to property that does not involve an assault or threat of violence.92If the accused establishes the Daviault defence to such a general intent crime on a balance of probabilities, he or she will be acquitted. The Daviault defence does not apply to crimes that require intoxication as an element of the offence because such a defence would be inconsistent with the mischief of the offence.93The third and most controversial intoxication defence is when the accused raises a Daviault defence to a violent general intent offence such as manslaughter, assault, or sexual assault. The Supreme Court’s decision in Daviault suggests that it would violate the accused’s rights under sections 7 and 11(d) of the Charter to convict a person who was
so extremely intoxicated at the time of the criminal act that he or she...