AI Hallucination Cases

This database tracks legal decisions1 I.e., all documents where the use of AI, whether established or merely alleged, is addressed in more than a passing reference by the court or tribunal.
Notably, this does not cover mere allegations of hallucinations, but only cases where the court or tribunal has explicitly found (or implied) that the AI produced hallucinated content.
in cases where generative AI produced hallucinated content – typically fake citations, but also other types of AI-generated arguments. It does not track the (necessarily wider) universe of all fake citations or use of AI in court filings.

While seeking to be exhaustive (452 cases identified so far), it is a work in progress and will expand as new examples emerge. This database has been featured in news media, and indeed in several decisions dealing with hallucinated material.2 Examples of media coverage include:
- M. Hiltzik, AI 'hallucinations' are a growing problem for the legal profession (LA Times, 22 May 2025)
- E. Volokh, "AI Hallucination Cases," from Courts All Over the World (Volokh Conspiracy, 18 May 2025)
- J-.M. Manach, "Il génère des plaidoiries par IA, et en recense 160 ayant « halluciné » depuis 2023" (Next, 1 July 2025) - J. Koebler & J. Roscoe, "18 Lawyers Caught Using AI Explain Why They Did It (404 Media, 30 September 2025)

If you know of a case that should be included, feel free to contact me.3 (Readers may also be interested in this project regarding AI use in academic papers.)

For weekly takes on cases like these, and what they mean for legal practice, subscribe to Artificial Authority.

State
Party
Nature – Category
Nature – Subcategory

Case Court / Jurisdiction Date ▼ Party Using AI AI Tool Nature of Hallucination Outcome / Sanction Monetary Penalty Details
Gittemeier v. Liberty Mutual Personal Insurance Company E.D. Missouri (USA) 16 October 2025 Lawyer Implied
Fabricated Case Law (2)
Misrepresented Case Law (1), Doctrinal Work (1)
Show Cause Order

"One week after filing its second motion for summary judgment, Liberty Mutual submitted a notice of errata identifying the erroneous Goodman and Chaudri citations and demonstrating legitimate citations to those cases. [ECF No. 50].3 While the Court acknowledges Liberty Mutual’s prompt notice disclosing the two most serious errors in its filing, the additional misquotations and mischaracterizations discussed above will not be disregarded. Liberty Mutual indicates that the errors were typographical and/or caused by vision impairment, but that explanation is simply not credible. The errors in Liberty Mutual’s filing are not ones in which a few letters or numbers were passed over or shuffled. Rather, the filing includes entire names, dates, court designations, and Westlaw citations that are completely off base, and various other inaccuracies cannot be explained by typographical or vision issues. Therefore, the Court will reserve its ruling on the motion for sanctions and will set a hearing requiring Liberty Mutual to show cause why it should not be sanctioned."

Source: Volokh
Serafin v. United States Department of State, et al. E.D. Missouri (USA) 16 October 2025 Pro Se Litigant Implied
Fabricated Case Law (3)
Misrepresented Case Law (2)
Warning
Polinski v. USA US Court of Federal Claims (USA) 15 October 2025 Pro Se Litigant Implied
Fabricated Case Law (3)
Warning

"On September 3, 2025, Plaintiff filed his response to the court’s order to file copies of the cases he cited (#7). Therein, Plaintiff avers he took “concrete remedial steps” to cure the time wasted by his use of artificial-intelligence-hallucinated case citations, including “submission of the verified opinions as exhibits” (#7 at 2). Indeed, Plaintiff’s response stresses how he“obtained authentic copies” of those cases and “attached” them as exhibits. See (id.).

Plaintiff did not attach any exhibits to his response to this court’s order. The court is convinced that those two case citations are AI-hallucinated. Plaintiff’s insistence that they exist—and that he provided copies of them to this court—is bewildering."

Nima Ghadimi v. Arizona Bank & Trust, et al. D. Arizona (USA) 15 October 2025 Pro Se Litigant Implied
Fabricated Case Law (2)
Warning
Charles C. Force v. Capital One, N.A., et al. M.D. Florida (USA) 15 October 2025 Pro Se Litigant Implied
Fabricated Case Law (3)
False Quotes Case Law (1)
Misrepresented Case Law (2)
Outdated Advice Overturned Case Law (1)
Filings stricken; Show Cause Order
Provincia del Chubut v. PRA Chubut (Argentina) 15 October 2025 Judge Implied
Misrepresented other (1)
Judgment annuled, new trial before different judge ordered

(Not an hallucination per se, but worth adding to the database anyway.)

Robert Allen Reed et al. v. Community Health Care et al. W.D. Washington (USA) 14 October 2025 Pro Se Litigant implied
Fabricated Case Law (5)
Warning
United States v. Glennie Antonio McGee S.D. Alabama (USA) 10 October 2025 Lawyer Ghostwriter Legal
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Outdated Advice Overturned Case Law (1)
Public reprimand, referral and order to notify jurisdictions; monetary sanction 5000

Folllowing a show cause order, Counsel admitted to having used the tool together with Google Search, and explained that, although he was aware of the issues with AI models like ChatGPT, he said he did not expect this tool to fall into the same issues.

The Court found Attorney James A. Johnson used Ghostwriter Legal to draft a motion that contained multiple fabricated case citations, misstated/false quotations attributed to authorities, and cited precedent that had been reversed by the Supreme Court. The Court found the conduct tantamount to bad faith and imposed sanctions under its inherent authority. Sanctions include an order to file, not under seal, this order "in any case in any court wherein he appears as counsel fortwelve (12) months after the date of this order."

Roy J. Oneto v. Melvin Watson, et al. N.D. California (USA) 10 October 2025 Lawyer Implied
Fabricated Case Law (3)
Monetary Sanction, Order to notify client, complete CLE, and Bar informed 1000 USD
David R. Pete v. United States Department of Justice, et al. E.D. Texas (USA) 10 October 2025 Pro Se Litigant Unidentified
Fabricated Case Law (2)
Magistrate Judge's recommendation adopted; in forma pauperis denied; plaintiff ordered to pay $405 filing fee within 10 days or the case will be dismissed.
Lipe v. Albuquerque Public Schools (2) D. New Mexico (USA) 8 October 2025 Lawyer Implied
Fabricated Case Law (1)
Misrepresented Legal Norm (1)
Warning

The court noted prior fabricated citations in plaintiff's earlier briefing (for which counsel had already been sanctioned). In the current filing the court found no fabricated citations but identified inaccurate legal contentions—e.g., a rule statement claiming withholding ready-to-produce material while seeking extra time is sanctionable under Fed. R. Civ. P. 37(b)—which the court found unsupported and incorrect. The court suspected plaintiff used AI again, but simply removed the citations. The court admonished counsel to review AI-generated work and comply with Rule 11 but did not impose additional sanctions here.

Souders v. Lazor Ohio CA (USA) 8 October 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Court rejected reliance on the cited authorities
Jose Villavicencio v. Judge Stephanie Mingo S.D. Ohio (USA) 7 October 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1), Legal Norm (1)
Warning
Douglas Stuart Queen v. Kansas City et al. D. Kansas (USA) 7 October 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning

The court admonished the pro se plaintiff, expressing concern he may be relying on artificial intelligence to draft filings and cite cases without confirming accuracy, and directed him to review Fed. R. Civ. P. 11; no specific fabricated citations or false quotations were identified in the opinion.

Ren v. Area 09 BCPAAB (Canada) 7 October 2025 Pro Se Litigant Implied
Fabricated Case Law (2)
Misrepresented Doctrinal Work (1)
Breach of Board's Code of Conduct
Thomas Dexter Jakes v. Duane Youngblood W.D. Pennsylvania (USA) 6 October 2025 Lawyer Implied
False Quotes Case Law (8), Exhibits or Submissions (1)
Misrepresented Case Law (1)
Monetary Sanction; Pro Hac Vice status revoked 5000 USD

Original Show Cause Order is here.

Source: Volokh
Smith v. Athena Construction Group, Inc. D.C. DC (USA) 3 October 2025 Lawyer Grammarly; ProWritingAid
Fabricated Case Law (1)
False Quotes Case Law (4)
Misrepresented Case Law (4)
Costs Order; Order to notify Bar 1

Show Cause Order is available here.

Tovar v. American Automatic Fire Suppression Inc. SC California (USA) 3 October 2025 Lawyer implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Outdated Advice Repealed Law (1)
OSC/motion denied; no sanctions imposed.

Court denied OSC/motion on procedural safe-harbor grounds but found defendants submitted miscited, non-existent, and inapposite authorities (and noted risk of AI-generated fake citations). Defendants accepted responsibility but no sanctions imposed.

Source: Volokh
The People v. Raziel Ruiz Alvarez CA California (USA) 2 October 2025 Lawyer Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Published order; monetary sanction payable by Counsel (who withdrew); State Bar notified 1500 USD

"When criminal defense attorneys fail to comply with their ethical obligations, their conduct undermines the integrity of the judicial system. It also damages their credibility and potentially impugns the validity of the arguments they make on behalf of their clients, calling into question their competency and ability to ensure defendants are provided a meaningful opportunity to be heard. Thus, criminal defense attorneys must make every effort to confirm that the legal citations they supply exist and accurately reflect the law for which they are cited. That did not happen here."

Source: Volokh
NewRez LLC v. Morton SC New York (USA) 2 October 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
No sanction
In the Interest of R.A. CA Iowa (USA) 1 October 2025 Lawyer Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Brief struck; Monetary penalty OR two hours of AI-specific CLE; referral to Bar 150 USD
Specter Aviation Limited v. Laprade CS Québec (Canada) 1 October 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Monetary sanction for procedural misconduct 5000 CAD

Monsieur Laprade filed a contestation containing multiple citations to non-existent authorities generated with the assistance of artificial intelligence. The Court found these to be fabricated (so-called "hallucinated") citations, constituting a manquement important to the conduct of the proceeding under art. 342 C.p.c., and imposed a 5,000$ sanction.

Ader v Ader SC New York (USA) 1 October 2025 Lawyer Unidentified
Fabricated Case Law (2)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Costs Order; Referral to Bar Authorities 1

"This case adds yet another unfortunate chapter to the story of artificial intelligence misuse in the legal profession. Here, Defendants' counsel not only included an AI-hallucinated citation and quotations in the summary judgment brief that led to the filing of this motion for sanctions, but also included multiple new AIhallucinated citations and quotations in Defendants' brief opposing this motion. In other words, counsel relied upon unvetted AI—in his telling, via inadequately supervised colleagues—to defend his use of unvetted AI."

Gavin B. Davis v. Chief Officer Gina Faubion, et al. W.D. Texas (USA) 1 October 2025 Pro Se Litigant Unidentified
Misrepresented Case Law (1), Doctrinal Work (1), Legal Norm (1)
Court accepted the R&R, dismissed the action with prejudice under 28 U.S.C. § 1915(e), and denied leave to amend.
Family Law Case Ghent CA (Belgium) 1 October 2025 Lawyer Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Reprimand

Story available here.

Fernando Oliveira v Ryanair DAC Workplace Relations Commission (Ireland) 1 October 2025 Pro Se Litigant Unidentified
Fabricated Case Law (2)
Misrepresented Case Law (7)
Conduct described as abuse of process

The Adjudication Officer found the complainant's submissions contained multiple inaccurate and non‑existent legal citations. The Respondent had flagged AI‑generated drafting and numerous phantom or misquoted determinations; the Officer concluded the complainant failed to establish a prima facie case and that the submissions contained egregious and misleading citations.

Tomlin v. State of New Mexico D. New Mexico (USA) 30 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
In re the Marriage of D.X. and S.P. CA California (USA) 30 September 2025 Pro Se Litigant Implied
Fabricated Case Law (7)
Warning

The appellate opinion and editor's note identify numerous incorrect or non-existent case citations in the appellant's filings. The court treated those citations as unreliable, found several to be fictitious or unlocatable, and declined to credit them in resolving the appeals.

Khoury et al v. Intermountain Health Care Inc. et al D. Utah (USA) 30 September 2025 Expert ChatGPT
Fabricated Case Law (1), Exhibits or Submissions (1)
Case dismissed

Case dismissed for "good cause" in light of motions to dismiss expert. Expert had confessed using ChatGPT.

In re: Todd Elliott Koger W.D. Pennsylvania (Bankruptcy) (USA) 30 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
One-year filing bar.

The Court observed that several authorities cited in the Kogers' pro se filings do not exist and appeared to be fabricated (noting possible use of AI), warned of Rule 9011 implications, and treated the filings as part of an abusive litigation strategy warranting dismissal and a one-year filing bar.

Kertesz v. Colony Tire Corp et al. D. New Jersey (USA) 30 September 2025 Lawyer Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Warning

Plaintiff's counsel filed a Notice of Errata admitting that erroneous citation and quotation errors in multiple briefs resulted from the attorney's use of generative AI. The Court refused to consider the amended briefs/errata for purposes of its decision and treated any propositions supported solely by the incorrect or made-up citations as unsupported. The Court declined to impose sanctions but warned the attorney that relying on AI without proper oversight can be sanctionable under the New Jersey Rules of Professional Conduct.

Button v. Doherty et al. S.D. New York (USA) 30 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (2)
Misrepresented Exhibits or Submissions (1)
Certification requirement for future AI-assisted filings.
Tajudin bin Gulam Rasul and another v Suriaya bte Haja Mohideen High Court (Singapore) 29 September 2025 Lawyer Unidentified
Fabricated Case Law (1)
Costs and order to inform client 800 SGD

CC cited a fictitious AI-generated case in written submissions. The Defendant's counsel located the error, CC admitted the authority was AI-generated and did not exist, and the Court found CC acted improperly, ordering personal costs of $800.

Munoz v. Lopez CA California (USA) 29 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Chapter Kris Jackson v. BOK Financial Corporation, et al. (2) N.D. Oklahoma (USA) 29 September 2025 Pro Se Litigant Implied
Fabricated Case Law (5)
False Quotes Case Law (1)
Show Cause Order
Jade Riley Burch v. HCA Healthcare D. Nevada (USA) 26 September 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Warning
Reddy v Saroya CA Alberta (Canada) 26 September 2025 Lawyer Implied
Fabricated Case Law (1)

The appellant's original factum contained references to seven cases that could not be located (six allegedly decisions of this Court). Respondent flagged the issue; appellant's counsel ultimately acknowledged a contractor-drafted factum and that a large language model may have been used. The Court allowed an amended factum and reserved costs, warning that use of LLM without verification may attract costs, contempt proceedings, or Law Society referral.

Oready, LLC (2) GAO (USA) 25 September 2025 Pro Se Litigant Implied
Fabricated Case Law (4)
Misrepresented Case Law (1)
Protests dismissed for abuse

Actually the fourth order in that case that pertains to hallucinations; a first, June 5 Order is only mentioned in a second, June 18 order that does not call out what appears to be hallucinated references.

Source: David Timm
Evans, et al. v. Robertson et al. (2) E.D. Michigan (USA) 25 September 2025 Pro Se Litigant Implied
Fabricated Case Law (3)
False Quotes Case Law (3)
Warning to both parties
Source: Volokh
Greenopolis Welfare Association (GWA) v. Narender Singh et al. Dehli High Court (India) 25 September 2025 Lawyer Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Petition withdrawn
Eric Andrew Perez v. Dr. Neil C. Evans, et al. S.D. New York (USA) 25 September 2025 Pro Se Litigant ChatGPT
Fabricated Case Law (1)
Misrepresented Case Law (1)
Warning
Source: Jesse Schaefer
Alexander Shaporov v. PIPPD P.O. Matthew Levine, et al. D. New Jersey (USA) 25 September 2025 Lawyer Implied
Fabricated Case Law (3)
False Quotes Case Law (1)
Misrepresented Case Law (2)
Show Cause Order

The district court independently found numerous inaccurate quotations and citations in Plaintiff's Opposition—misquoted language attributed to binding Third Circuit authority, Westlaw citations and dates that were incorrect or non-existent, and miscited pincites. The court concluded the pattern suggested the brief may have been prepared using generative AI without adequate verification and ordered counsel to show cause under Rule 11 and ethical rules. The court preserved the inaccuracies in the official opinion but removed links to invalid citations.

Beschluss 2-13 S 56/24 LG Frankfurt a. M. (Germany) 25 September 2025 Lawyer Unidentified
False Quotes Case Law (1)

Story available here.

BFG aka Byline Financial v. Pierce RE Holdings & Brewster N.D. Illinois (USA) 24 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Kenisha Black v. Mississippi DRS & Howard S.D. Mississippi (USA) 24 September 2025 Lawyer Unidentified
Fabricated Case Law (1)
Court accepted corrected briefs

Plaintiff's counsel admitted that the opening memorandum and reply brief contained false AI-generated content. Counsel filed corrected memoranda; the court noted a Rule 11 violation but accepted the corrections and declined to impose sanctions or require additional briefing.

Source: Jesse Schaefer
Melinda L'Shay Johnson v. MINI of Las Vegas D. Nevada (USA) 24 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
T.M. v. M.M. CA Indiana (USA) 24 September 2025 Pro Se Litigant Implied
Fabricated Case Law (5)
False Quotes Case Law (1)
Misrepresented Exhibits or Submissions (1), Legal Norm (1)
Warning

The Court preserved the invalid citations in the opinion as they are part of the record, admonished that fabricated or incorrect citations frustrate review and may lead to reprimand or sanction.

Puerto Rico Soccer League NFP, Corp., et al. v. Federación Puertorriqueña de Futbol, et al. D.C. Puerto Rico (USA) 23 September 2025 Lawyer Unidentified
Fabricated Case Law (6)
False Quotes Case Law (25)
Misrepresented Case Law (24)
Order to pay opposing counsel's fees 24492 USD

In the Order, the court stated: "A simple Google search would have shown the problems in some of Plaintiffs’ citations. In other instances, a quick search of the opinion Plaintiffs cited to would have revealed problems. Levying appropriate sanctions here promotes deterrence without being overly punitive, as contemplated by Rule 11(c)(4).

The Court notes that, rather than showing contrition, the Memorandum in Compliance strikes a defiant and deflective tone. (Docket No. 190). It also contains more of the errors that plagued Plaintiffs’ previous four filings. For example, in the “Legal Standard” section of the memorandum, Plaintiffs cite to two cases for the proposition that sanctions are an “extreme remedy” appropriate for instances of prejudice or bad faith. One case makes no mention of sanctions and neither contain the proffered quote Id. at 3. The Court finds it problematic that Plaintiffs responded to a show cause order to address the problem of multiple inaccurate citations by providing a response containing more erroneous citations."

Monetary sanction was decided in a subsequent decision dated 23 September 2025, available here.

Stile Carpentry Ltd. v. 2004424 Ontario CA Ontario (Canada) 23 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1), Exhibits or Submissions (1), Legal Norm (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Sentenza del 23.09.2025 Tribunale di Latina (Italy) 23 September 2025 Lawyer Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Monetary Sanction 2000 EUR
Source: LeggeZero