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 a party relied on hallucinated content or material.

As an exception, the database also covers some judicial decisions where AI use was alleged but not confirmed. This is a judgment call on my part.
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 (1312 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 have any questions about the database, a FAQ is available here.
And 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.)

Based on this database, I have developped an automated reference checker that also detects hallucinations: PelAIkan. Check the Reports Report icon in the database for examples, and reach out to me for a demo !

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 Report(s)
Edward Starski v. Chandler Holderness CA Appeals (USA) 18 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Warning
Arabyads Holding Limited v. Gulrez Alam Marghoob Alam ADGM (UAE) 18 December 2025 Lawyer Implied
Fabricated Case Law (2)
Misrepresented Case Law (4)
Mon 282508

MIO produced a prolix Defence containing multiple non-existent, miscited and misapplied authorities. The Court found AI-driven research produced hallucinatory results and that MIO failed adequately to verify authorities, amounting to reckless conduct warranting an indemnity costs order.

Wireless Investors LLC v. Semtech Incorporated, et al. D. Arizona (USA) 18 December 2025 Lawyer Implied
False Quotes Case Law (1)
Misrepresented Case Law (1)
Warning
Source: Jesse Schaefer
Friend v. Serpa CA Florida (USA) 17 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Source: Jesse Schaefer
Halpern v. Federal Reserve Bank of New York, et al. N.D. Illinois (USA) 17 December 2025 Pro Se Litigant Implied
False Quotes Case Law (1)
Russel Williams Home Services LLC v. Minleon International (USA) Limited LLC, et al. M.D. Pennsylvania (USA) 17 December 2025 Lawyer Implied
False Quotes Case Law (2)
Order to Show Cause
Burlingame v. Argo Private Client Group, Ltd. et al. S.D. New York (USA) 17 December 2025 Lawyer Implied
Fabricated Case Law (1)
False Quotes Case Law (2)
Misrepresented Case Law (1)
L.A. Housing Outreach, LLC v. Medoff CA California (USA) 17 December 2025 Lawyer Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Reply brief struck; monetary sanction; State Bar referral 5070 USD

The court found that the majority of legal authorities in appellant counsel's reply brief were incorrect or did not support the propositions for which they were cited. The court struck the reply brief, imposed monetary sanctions of $5,070, and directed a copy of the opinion be forwarded to the State Bar.

Source: Jesse Schaefer
Angelica E. Cruz et al. v. United States of America C.D. California (USA) 16 December 2025 Lawyer Implied
Fabricated Case Law (1)
Order to Show Cause
In re Ricardo Andres Romeu CA Texas (USA) 16 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Taylor v. Prince George’s County, Maryland D. Maryland (USA) 16 December 2025 Lawyer Implied
False Quotes Case Law (1)
Misrepresented Case Law (2)
Report
Plaintiff's Response
Dorsey v. Jones Delaware C. Ch. (USA) 16 December 2025 Lawyer Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Order to certify future filings re: AI
McMillian v. Zimmer US, Inc S.D. New York (USA) 16 December 2025 Lawyer Unidentified
Fabricated other (1)
Adverse Costs Order 9000 USD
Source: Jesse Schaefer
Michael Redwine v. Unum Life Insurance Company of America W.D. Virginia (USA) 16 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Source: Jesse Schaefer
Holmes Family Trust v. Multnomah County Assessor Oregon Tax Court (USA) 16 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Source: Jesse Schaefer
Pakuza v Workers' Compensation Regulator Queensland IRC (Australia) 16 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
PRM Group, Inc. v. Paralegal Bootcamp LLC D. Maryland (USA) 16 December 2025 Lawyer Implied
Fabricated Case Law (1)
Misrepresented Case Law (1), other (1)
Show Cause Order
Vicki Boomer v. Hospital Employees' Union and Interior Health Authority British Columbia LRB (Canada) 16 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1), Legal Norm (1)
Misrepresented Legal Norm (1)
Liza Gardner v. Sean Combs, et al. D. New Jersey (USA) 15 December 2025 Lawyer Unidentified
Fabricated Case Law (1)
Monetary fine; Bar Referral; Order to serve order to Client 6000 USD

Counsel had already been sanctioned in different case, and professed having gone through CLE on generative AI.

Source: Robert Freund
Sayali Kulkarni & Abhijit Kulkarni v. Merit Systems Protection Board CA Federal Circuit (USA) 15 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Affirmed the Board; granted motions to strike the Kulkarnis' informal reply briefs containing the false citations/quotes
Report
Plaintiff's Informal Brief
Roll Q/25/0025 Gent (Belgium) 15 December 2025 Lawyer Implied
Fabricated Case Law (3)
Hearing on possible sanction
Braica v. Frankowski (Anthony Braica v. Tom Frankowski) D. Connecticut (USA) 15 December 2025 Pro Se Litigant Implied
Fabricated Case Law (2)
False Quotes Case Law (2)
Misrepresented Case Law (7)
Outdated Advice Overturned Case Law (1)
Briefs struck; warning
Christina Garcia v. Atwater Elementary Teachers Association California PERB (USA) 15 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (3)
Warning
Harvey v. Torrent Leasing & U.S. Bank D. Nevada (USA) 15 December 2025 Pro Se Litigant ChatGPT
False Quotes Case Law (1)
Misrepresented Case Law (1)
Warning
Robert W. Williams, Sr. v. Assistant District Attorney John R. Canavan, et al. M.D. Pennsylvania (USA) 15 December 2025 Pro Se Litigant Unidentified
False Quotes Case Law (1)
Misrepresented Case Law (1)
Warning
Howell Management Services, LLC v. Vashisht-Rota CA California (USA) 15 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Fine and adverse costs order 64235 USD
Source: Jesse Schaefer
Bégin-Létourneau c. Syndicat des spécialistes et professionnels d'Hydro-Québec TAT (Canada) 15 December 2025 Pro Se Litigant Implied
Fabricated Case Law (2)
St-Roch c. Andritz Hydro Canada inc. TAT (Canada) 15 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Source: Courtready
Tsafrir v. Goldberg Supreme Court (Israel) 14 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
3000 ILS
Johnson / Estate of Fisher v. City of Annapolis D. Maryland (USA) 13 December 2025 Lawyer Implied
Fabricated Case Law (1)
Misrepresented Case Law (1), Exhibits or Submissions (1)
(Attorney was dismissed by its client)
Report
City's Motion
Source: Volokh
Troy Allen Berg v. Mandi Marie Wondra D. Oregon (USA) 12 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Outdated Advice Overturned Case Law (2)
Warning
Jordan v. Beskrone (In re Prehired LLC) D. Delaware (Bankruptcy) (USA) 12 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (2)
Second Amended Complaint dismissed
Source: Jesse Schaefer
A.M., F.A. c/ C.N.H y otros CA Río Negro (Argentina) 12 December 2025 Lawyer Implied
Fabricated Case Law (5)
Misrepresented Case Law (1)
Admonishment
Mr T De Carvalho Ferreira v Magic Life Limited & Ors Employment Tribunals (Reading) (UK) 12 December 2025 Lawyer Unidentified
Fabricated Case Law (1)
Warning
McLain v. Board of County Commissioners of Sedgwick County, Kansas, et al. D. Kansas (USA) 11 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Warning
Report
Plaintiff's Motion
Preston House v. TH Foods, Inc. D. Nevada (USA) 11 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Admonishment
Sean Gottlieb v. Adtalem Global Education N.D. Illinois (USA) 10 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Order to Show Cause
Report
Plaintiff's Second Memorandum
Russell v. Mells CA Florida (USA) 10 December 2025 Lawyer Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Bar Referral

"Unfortunately, we're finding this problem arising more and more frequently […] When a lawyer cites imaginary legal authorities to our court as if they were law, we are compelled to refer that lawyer to the Bar because of the professional rules of conduct.

It doesn't take much moral imagination to understand why. As judges, we rely on attorneys to ethically represent their clients. We expect that representation to be zealous, honest, and competent. Indeed, lawyers owe the courts and their clients a duty to practice with competence and candor. By signing an appellate brief, a lawyer certifies that he or she has read the document and that to the best of the lawyer's knowledge, information, and belief there are "good grounds to support the document."

These ethical requirements are not excused simply because a computer program generated a faulty or misleading legal analysis. Nor is it an excuse that the attorney did not intend to mislead the court. "To state the obvious, it is a fundamental duty of attorneys to read the legal authorities they cite in appellate briefs or any other court filings to determine that the authorities stand for the propositions for which they are cited."

Obviously, that didn't happen when Ms. McLane filed this answer brief. Instead, counsel "fundamentally abdicated" her duty to the court and her client when she submitted this filing without verifying that the three cases cited in her brief said what she claimed they said. Accordingly, it is our duty to refer this matter to the Florida Bar to proceed as it deems appropriate."

Source: Volokh
James Fahey v. Wally’s Las Vegas, LLC, et al. D. Nevada (USA) 10 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Warning
Report
Plaintiff's Response
South Side Area School District et. al v. Pennsylvania Human Relations Commission Pennsylvania CC (USA) 10 December 2025 Lawyer Implied
False Quotes Case Law (1)
Misrepresented Case Law (1)

See story here and here.

Sharky’s Sports Bar, et al. v. Village of Mt. Morris, Illinois, et al. N.D. Illinois (USA) 10 December 2025 Lawyer Implied
Misrepresented Case Law (2)
Warning
Report
Defendants' Motion to dismiss
Russell v. Mells CA Florida (USA) 10 December 2025 Lawyer Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Order to Show Cause; Bar Referral
Huseyin Turgut v The Minister of Citizenship and Immigration Federal Court (Canada) (Canada) 10 December 2025 Lawyer Implied
Fabricated Case Law (1)
Withdrawal of arguments based on the disputed citations
Mr J Harrison v Mr D May t/a Leeds Gymnastics Academy Employment Tribunals (Leeds) (UK) 10 December 2025 Pro Se Litigant ChatGPT
Fabricated Case Law (1)
Tribunal awarded claimant a preparation time order of £2,178; payment stayed pending outcome of EAT appeal. 2178 GBP
D (A Child) (Recusal) Court of Appeal (UK) 9 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (2)
Warning
Christian Dusablon v. Hugh A. Gibbs and Union Logistics, LLC S.D. New York (USA) 9 December 2025 Lawyer Implied
Fabricated Case Law (1)
Warning; Order to Certify validity of future citations
Report
Plaintiff's Memorandum of Law
Scott M. Boger v. City of Harrisonburg, Virginia, et al. W.D. Virginia (USA) 9 December 2025 Pro Se Litigant Implied
False Quotes Case Law (1)
Misrepresented Case Law (1)
Warning
Case n° 2512468 TA Grenoble (France) 9 December 2025 Pro Se Litigant Unidentified
Omkara Assets Reconstruction Private Limited v. Gstaad Hotels Private Limited Supreme Court (India) 8 December 2025 Lawyer Unidentified
Fabricated Case Law (1)
Warning (during hearing)

Story can be found here.

S. Peggie v. Fife Health & Dr. B. Upton Employment Tribunal (Scotland) (UK) 8 December 2025 Judge Implied
False Quotes Case Law (2)

Allegations that these are made-up quotes involving AI were aired in various blogs and online comments (see, e.g., here and here).

The tribunal eventually issued a correction, and then claimed that it was not AI but the result of "an exchange of correspondence between [the judge] and a judicial colleague" - which raises more questions than it answers.

⚠ Alleged AI Use