Ontario Superior Court Weighs In On The Use Of AI In The Courtroom

On May 6, 2025, the Ontario Superior Court of Justice (the Court) released its decision in Ko. v Li, 2025 ONSC 2766, commenting on the appropriate use of artificial intelligence (AI) in the court room. The case is a cautionary tale for the legal community with respect to reliance on AI technologies in preparation of court documents.

The case involved two estates applications and one family law application. Counsel for the applicant delivered a factum citing several decisions. However, the factum contained multiple errors: (i) one hyperlink directed to the wrong case; (ii) some citations referred to cases entirely unrelated to the issues; (iii) one hyperlink led to a “404 Error” page on CanLII; and (iv) one citation referenced a case that actually reached the opposite conclusion from the one advanced in the submission.

During the oral submissions, counsel for the applicant relied on these cases in support of her client’s arguments. When questioned by the Court, she was unable to provide citations or printed copies of the cases referred to in her factum.

The Court began its decision by addressing the “serious issue” presented by these submissions. The Court noted that the factum may have been generated using AI, and that counsel for the applicant “might not have checked to make sure the cases were real or supported the propositions of law which she submitted to the court in writing and then again orally.”

The Court emphasized that “it is the lawyer’s duty not to fabricate case precedents and not to mis-cite cases for propositions that they do not support.” The Court concluded that counsel for the applicant “may have committed grave breaches of her duties that may amount to contempt in the face of the court.”

As a result, the Court ordered counsel to show cause why she should not be cited for contempt.

Summary By: Victoria Di Felice