Supreme Court to rule on whether extreme intoxication can be used as a criminal defence

The highest court in the country heard arguments Tuesday on the constitutionality of a controversial section of the Criminal Code which says self-induced intoxication cannot be used as a defence.

At issue were the cases of two Ontario men: Thomas Chan and David Sullivan.

In 2015, Chan — then a 19-year-old student — took a large dose of psilocybin (the compound in so-called "magic mushrooms") before stabbing his father to death and seriously injuring his father's partner at their home in Peterborough. 

Two years prior, Sullivan — a Whitby man with a criminal record — attempted suicide by taking the prescription medication Wellbutrin but ended up stabbing his mother under the influence of the drug. She survived the assault but later died of an unrelated heart attack.

Both men pleaded not guilty and were convicted. The Ontario Court of Appeal overturned those decisions.

It found that Section 33.1 of Canada's Criminal Code, which says an accused cannot claim a defence by reason of self-induced intoxication, infringed on the rights of both Chan and Sullivan under the Charter of Rights and Freedoms.

The court also ruled that the law banning an intoxication defence does not qualify as a reasonable limit on charter rights under Section 1 of the charter.