Deterring AI Hallucinations – The Ontario Courts Weigh In

The facts matter. Perhaps not always, at least in the court of public opinion. But in a court of law, they reign supreme—no matter how unfortunate those facts may be for counsel.

Justice Myers of the Ontario Superior Court provided a stark reminder of this principle in a decision released May 20 in Ko v. Li (2025 ONSC 2965). As we recapped previously, Justice Myers had ordered counsel, who had relied on AI-hallucinated cases in both a factum and oral submissions before him, to attend for a show cause hearing to determine whether or not she should be held in contempt for violating Rule 4.06.1 (2.1) of the Rules of Civil Procedure, which requires counsel to certify the authenticity of cited authorities.