In some cases, intoxication can be relevant to refute the mental or ‘mens rea’ element of a criminal offence. An important distinguishing factor in the defence of intoxication is whether a person was voluntarily intoxicated. If an accused unknowingly consumes an intoxicating substance or had an unexpected reaction to medication, this will be considered involuntary intoxication, which could negate the intent of the offence. For example, if someone was forced to ingest an intoxicating substance or it was surreptitiously put into food or drink they ingested, the defence of involuntary intoxication will take effect. However, if a substance was voluntarily consumed and the person ought to reasonably have known that it was an intoxicant, an involuntary intoxication defence will fail. This was decided in court of appeal cases such as R v Chaulk and R v Abel.
Voluntary intoxication is more complex. Simply being intoxicated when you commit an offence is not in itself a defence. There is a very small percentage of cases where the intoxication is so extreme that a defence of voluntary intoxication is available. Voluntary intoxication can only be used in circumstance of a general intent offence, rather than specific intent. General intent offences only require the accused intended to do the act in question (for example, assault will only require touching another person without consent), while specific intent offences involve the intention of something more (for example murder requires intentional infliction of harm and intention to kill). If an accused wishes to use voluntary intoxication as a defence, the burden of proof then shifts to the defendant to prove on a balance of probabilities that they were so intoxicated that they lacked the mens rea to commit the offence. Even if an accused was intoxicated while committing a general intent offence, self-inducted intoxication will not be a defence if the accused departed from the standard of care reasonably required in Canadian society. As seen in R v Holland, simply producing evidence of intoxication is not enough to establish this defence. So, while intoxication CAN be used as a defence in some cases, it is under very strict circumstances, and it is up to the accused to convince the Court that it should be available to them.
Ron Ellis Law is a criminal defence firm based in London, Ontario and we practice criminal defence law all over Southwestern Ontario, including Grand Bend, Sarnia, Woodstock and Kitchener.