A hallucinated case citation isn't a hypothetical risk — Canadian courts have already named the failure mode, written sanctions for it, and in Ontario's case, changed the Rules of Civil Procedure to catch it before it does damage.
Key takeaways
The Federal Court defines the failure mode precisely: “facts, citations, and other content generated by AI that are not true, and have been fabricated by AI in response to a prompt or request” — a hallucination. (Federal Court, Notice to the Parties and the Profession, May 7 2024) Ontario’s Superior Court of Justice is blunter about how it actually shows up in practice: “most often, it occurs when counsel or litigants carelessly rely on fictitious authorities generated by AI, commonly referred to as ‘hallucinations’. Hallucinations can consist of non-existent cases, mischaracterizations of case law, and fabricated quotations.” (Ontario SCJ, Consolidated Civil Practice Direction)
Ontario’s Consolidated Provincial Practice Direction states plainly that “it is the responsibility of all counsel and litigants to guarantee accuracy when preparing materials for use in court proceedings, and particularly when using AI, regardless of whether they directly interacted with the technology… the court will not tolerate inadvertence in this regard.” (Ontario SCJ, Consolidated Civil Practice Direction) Where that duty is breached, the range of responses is spelled out: “the court’s powers include, but are not limited to, public reprimand of the counsel or litigant, the imposition of cost orders, adjourning a hearing or dismissing the matter, the initiation of contempt proceedings, and in regards to counsel, referral to the Law Society of Ontario. In each instance, the court’s response will depend on the specific facts and circumstances of the case.”
That last sentence matters: a hallucinated citation does not carry one fixed penalty. Dismissal is one option on a list that also includes a reprimand or a cost order, and which one applies turns on the facts — including, presumably, whether the error was caught before it affected the proceeding, and whether it looks like carelessness or something closer to deception.
This is the clause that removes the easiest excuse. A lawyer who asked a junior associate, a student, or an outside service to prepare a factum, and never touched an AI tool personally, is still caught by Ontario’s rule if the finished product contains a fabricated authority. The Federal Court reaches a version of the same result through its successor-counsel duty: a lawyer taking over a file must “make best efforts to ascertain whether any such content has been included” in material they inherited, rather than being able to disclaim responsibility for what a predecessor filed. (Federal Court, Notice to the Parties and the Profession, May 7 2024)
Ontario did not stop at describing the problem — it amended the Rules of Civil Procedure, filed October 15, 2024 and in force December 1, 2024. Rule 06.1(2.1) now requires a factum to “include a statement signed by the party’s lawyer… certifying that the person signing the statement is satisfied as to the authenticity of every authority cited in the factum.” Subrule (2.2) then gives that certification a shortcut: an authority published on a government website, by a government printer, on CanLII, on a court’s website, or by a commercial publisher of court decisions “is presumed to be authentic… absent evidence to the contrary.” (Ontario SCJ, Consolidated Civil Practice Direction) A citation an AI tool invented cannot clear that bar — it will not appear on any of those sources, because it does not exist, and the presumption is rebuttable rather than automatic in any event.
Alberta addresses the identical failure mode — a fabricated authority reaching a court submission — through its Reliance clause rather than a certification rule: parties must “rely exclusively on authoritative sources such as official court websites, commonly referenced commercial publishers, or well-established public services such as CanLII.” (Alberta Courts, Tri-Court Notice) The practical effect is similar to Ontario’s presumption-of-authenticity list, but Alberta frames it as a duty of reliance rather than a signed certification, and attaches no named sanctions regime of its own the way Ontario’s Practice Direction does.
It is worth separating two things that can look alike on the page. A lawyer who cites a real case but gets a paragraph number wrong, or misreads what it decided, has made an ordinary research error — the kind civil procedure has always dealt with through argument and correction. A hallucinated authority is different in kind: the case, the quotation, or the holding simply does not exist anywhere to be misread. Ontario’s own language draws this distinction — “non-existent cases, mischaracterizations of case law, and fabricated quotations” are listed as three separate things a hallucination can consist of, and only the middle one resembles an ordinary mistake. (Ontario SCJ, Consolidated Civil Practice Direction) That distinction is part of why the sanctions range from a light-touch reprimand up to contempt: the court is being asked to judge not just that an error occurred, but what kind.
A factum filed in an Ontario proceeding cites a decision that reads as a plausible Superior Court ruling but does not exist — it was generated by an AI tool asked for supporting case law. Under Rule 06.1(2.1), the lawyer signing the factum has already certified they are satisfied as to its authenticity; if it turns out they never checked it against CanLII or a government source, that certification itself becomes the problem, independent of who typed the citation into the document. The range of consequences the Practice Direction lists then applies — from a reprimand up to referral to the Law Society of Ontario — with the specific outcome turning on whether this looks like a one-off oversight or a pattern. This is a materially different exposure than the same mistake in a jurisdiction, like Alberta, with a reliance duty but no equivalent certification and sanctions regime.
Related: the Federal Court’s rules on AI in filings, Alberta courts and AI-generated material, and can lawyers use generative AI in Canada
No. Ontario's Practice Direction lists dismissal as one of several possible court responses — alongside reprimand, cost orders, adjournment and contempt proceedings — and states that the response depends on the specific facts and circumstances.
The specific certification requirement in Rule 06.1(2.1) is tied to a factum. A related authenticity presumption in 06.1(2.2) covers authorities from government, CanLII, court, or commercial-publisher sources — it is not a blanket rule for all filings.
No. Ontario's rule applies “regardless of whether they directly interacted with the technology,” and the Federal Court imposes a parallel duty on successor counsel to check inherited material for undisclosed AI content.
The same verification discipline applies to any AI-assisted research relied on outside a courtroom.
