AI hallucinations in court: the cases that matter.
The leading decisions where courts sanctioned or disciplined lawyers for AI-fabricated citations, with what happened, the outcome and the lesson. Each entry links to a source.
| Case | Court · date | What happened | Outcome | Lesson |
|---|---|---|---|---|
| Withers v. City of Aberdeen Vaquill tracker ↗ | N.D. Miss. June 2026 | Lawyers on both sides filed briefs containing AI-hallucinated material. | Four lawyers sanctioned | Check the other side’s citations too, and your own. |
| Nebraska Supreme Court (divorce appeal) Vaquill ↗ | Neb. April 16, 2026 | 57 of 63 citations in a brief were defective; the lawyer initially attributed the brief to traditional research. | Temporary licence suspension pending disciplinary hearing | Concealment can cost you your licence. |
| Whiting v. City of Athens Sixth Circuit opinion ↗ | 6th Cir. March 13, 2026 | Appellate briefs contained more than two dozen fabricated citations and misrepresentations of the record. | $15,000 per attorney, opposing party’s appellate fees, double costs, disciplinary referral | Lawyers must personally read and verify every citation. |
| Fletcher v. Experian Vaquill tracker ↗ | 5th Cir. February 2026 | Briefing contained fabricated quotations, reportedly despite use of legal research AI tools. | $2,500 sanction | “The tool was built for lawyers” is no defence. |
| Couvrette v. Wisnovsky Vaquill ↗ | D. Or. December 2025 | Three summary-judgment briefs cited 15 nonexistent cases and 8 fabricated quotations; counsel refiled rather than withdrawing. | $110,204.38 combined sanctions and fees; case dismissed with prejudice; bar notified | Resisting after notice multiplies the cost. |
| Noland v. Land of the Free, L.P. Vaquill tracker ↗ | Cal. Ct. App. (2d Dist.) September 2025 | Appellate briefing contained fabricated quotations attributed to real cases. | $10,000 sanction and referral to the State Bar | Fake quotations inside real cases are a common failure. |
| Coomer v. Lindell Vaquill tracker ↗ | D. Colo. July 2025 | Brief contained nearly thirty defective citations. | $3,000 fine per attorney (a later order in 2026 added further sanctions) | High-profile matters attract high-profile scrutiny. |
| Johnson v. Dunn Vaquill tracker ↗ | N.D. Ala. July 2025 | Filings by attorneys at a large firm included fabricated citations generated with ChatGPT. | Attorneys removed from the case and referred to the bar | Firm reputation does not shield individual lawyers. |
| Lacey v. State Farm Vaquill tracker ↗ | C.D. Cal. (Special Master) May 2025 | Brief contained multiple bogus citations produced with AI tools across two firms. | $31,100 in sanctions | Large firms are not immune; supervision gaps are costly. |
| Wadsworth v. Walmart Inc. Vaquill tracker ↗ | D. Wyo. February 2025 | Motions in limine cited eight nonexistent cases generated by a firm’s in-house AI tool. | $5,000 total sanctions; one pro hac vice admission revoked | Signing counsel share responsibility for what they sign. |
| Kohls v. Ellison Vaquill tracker ↗ | D. Minn. January 2025 | An expert declaration cited academic sources that did not exist, drafted with AI assistance. | Declaration excluded | The risk extends to experts and evidence, not only briefs. |
| Gauthier v. Goodyear Tire & Rubber Co. Vaquill tracker ↗ | E.D. Tex. November 2024 | Response cited nonexistent cases and fabricated quotations produced with an AI tool. | $2,000 penalty and AI-related CLE | Every major tool has been implicated, not only ChatGPT. |
| Park v. Kim Vaquill tracker ↗ | 2d Cir. January 2024 | Reply brief cited a nonexistent case generated by ChatGPT. | Referral to the court’s Grievance Panel | Appellate courts treat this as a professional-conduct matter. |
| People v. Crabill Vaquill tracker ↗ | Colorado Presiding Disciplinary Judge November 2023 | Lawyer filed a motion with ChatGPT-fabricated cases and was found to have misled the court about it. | Suspension from practice | Dishonesty about AI errors turns a mistake into misconduct. |
| Mata v. Avianca, Inc. Vaquill tracker ↗ | S.D.N.Y. June 2023 | Brief cited six nonexistent decisions generated by ChatGPT, with fabricated quotations. | $5,000 sanction on lawyers and firm | The case that put the profession on notice. |
Compiled from court opinions and public trackers; summaries are simplified. For the full record, see Damien Charlotin’s AI Hallucination Cases database. Free to cite with a link to this page.
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Read the guideQuestions
How many court decisions involve AI hallucinations?
Legal researcher Damien Charlotin’s public database tracked roughly 1,490 decisions worldwide by May 2026, more than 1,000 of them in US courts, in which a party relied on AI-hallucinated content and the court responded. Numbers continue to grow.
What is the largest AI hallucination sanction so far?
Reported as Couvrette v. Wisnovsky (D. Or.), where two lawyers were ordered to pay a combined $110,204.38 in sanctions and fees after briefs cited 15 nonexistent cases.
Has any lawyer lost their licence over AI citations?
In April 2026 the Nebraska Supreme Court temporarily suspended an attorney pending a disciplinary hearing after 57 of 63 citations in a brief were found defective. Earlier, a Colorado lawyer was suspended in a disciplinary matter involving ChatGPT-fabricated cases and misleading statements to the court.