Effective September 1, 2026, the Ontario Rules of Civil Procedure (the “Rules”) were amended to include major changes to Rule 4.06.1 and Rule 53.03 pertaining to artificial intelligence use in the modern legal landscape. Designed as a strict “anti-hallucination” gatekeeper for the provincial courts, these sweeping amendments to the Rules of Civil Procedure outlaw blind copying and pasting from artificial intelligence. By forcing lawyers and expert witnesses to legally sign off on the authenticity of every single citation, Ontario is sending a crystal-clear message: while AI shortcuts can be tempting, the financial and reputational costs of a digital hallucination will land squarely on the litigant’s shoulders.
During the initial advent and proliferation of AI, legal decisionmakers were forced to use existing ethical rules to hand down punishments for practitioners, experts, and individuals who presented AI hallucinated authorities as authentic. However, with these amendments to the Rules, decisionmakers will have a concrete framework to deal with when dealing with the use of AI in their courtrooms. This is important for clients to understand, because there are harsh penalties in place for improper AI use that could have serious negative implications on their case such as elevated costs sanctions. Additionally, being in violation of these new rules can cause severe procedural damage to the case, like disregarding or striking out non-compliant court materials that can result in delays.
The New “Verification Gate”
The new amendments introduce a strict procedural gatekeeper under Rule 4.06.1., and as such, the excuse of “the computer told me so” has been codified as inappropriate.
It is no secret that over the past year, the Ontario courts have been forced to deal with numerous cases where AI hallucinated authorities that don’t exist have been presented as actual authorities meant to be relied on by a decision-maker. Therefore, these new amendments serve as both a remedial and proactive measure to ensure that only real authorities are cited in Ontario’s courtrooms.
Rule 4.06.1 deals with factums, which are the core legal argument court documents in most civil cases. Under the new Rule 4.06.1. a party’s lawyer must sign a statement that every legal authority referred to in the factum is genuine, and stands for the proposition it says it stands for. In Kapahi Real Estate Inc. v Elite Real Estate Club of Toronto Inc., 2026 ONSC 1438, a factum contained seven fake quotations from real cases, and the Court did not accept the lawyer’s argument that they did not use AI.
A Heightened Expert’s Duty
Expert witnesses often play a crucial role in complex civil litigation matters, and their testimony can often “make or break” a case. Rule 53.03 extensively deals with the procedure expert witnesses must follow.
Due to the important nature of their testimony, as part of Rule 53.03, expert witnesses are required to sign an Acknowledgement of Expert’s Duty, with the court-provided Form 53. The new Form 53 requires an expert to certify the authenticity of every authority or document used to form their opinion, and that every quotation accurately reproduces the text of the authority.
Practical Takeaway
AI has become a common tool for drafting, research, and document preparation, but Ontario’s new rules make it clear that convenience does not replace accountability. Lawyers and expert witnesses must now formally certify that the authorities and quotations they rely upon are authentic and accurately represented. If inaccurate or fabricated authorities make their way into court materials, there can be significant consequences.
AI-generated content should be treated as a starting point, not a final product. Whether information is prepared by a lawyer or an expert, accuracy and verification remain essential because responsibility ultimately rests with the people advancing the case before the court.
About the Author
Cheyanna Sammy is an associate in Soloway Wright LLP’s litigation group. She joined the firm in 2026 after completing her summer term and articles with Soloway Wright. Cheyanna holds a J.D. from the University of Ottawa Faculty of Law, where she graduated Cum Laude with a specialization in public law, as well as a B.A. (Hons.) and M.A. in History from the University of Toronto. She was called to the Ontario Bar in June 2026.
