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 (1247 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)
Saqib Kafeel v. Apple Inc., et al. N.D. California (USA) 1 April 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Patrick Hrdlichka v. Samantha Bengston CA Arkansas (USA) 1 April 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
In the Interest of W.G., Minor Child CA Iowa (USA) 1 April 2026 Pro Se Litigant Perplexity
Fabricated Case Law (1)
Misrepresented Case Law (1)
Chelsea Montes v. Suns Legacy Partners LLC D. Arizona (USA) 31 March 2026 Lawyer Implied
Fabricated Case Law (6)
False Quotes Case Law (2)
Adverse Costs Order; CLE; Notification
Source: Robert Freund
Edward C. Allen v. Western Governors University, et al. D. Nevada (USA) 31 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (4)
Misrepresented Case Law (3)
Case dismissed with prejudice; Adverse Costs Order 1 USD
Rushing v. Rushing et al. CA Minnesotta (USA) 31 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
CA greenlighted dismissal of case for AI misuse
Rosa Maria Cabrera Thompson v. Seattle Public Schools W.D. Washington (USA) 31 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Order to Show Cause
Federal Trade Commission v. James D. Noland, Jr., et al. D. Arizona (USA) 31 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Quandel Construction Group, Inc. v. Hunt Construction Group, Inc. S.D. Ohio (USA) 31 March 2026 Lawyer Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Order to Explain
Heimkes v. Fairhope Motorcoach Resort Condominium Owners Association, Inc. S.D. Alabama (USA) 31 March 2026 Lawyer Cocounsel (Westlaw)
Fabricated Case Law (1)
Misrepresented Case Law (1)
Outdated Advice Overturned Case Law (1)
Reprimand; Order to file order in subsequent cases; Bar Referral; Adverse Costs Order 55597
Danuta Dec v. Homeland Security 7th Cir. CA (USA) 30 March 2026 Lawyer Implied
Fabricated Case Law (2)
False Quotes Case Law (1)
Admonishment
Source: Robert Freund
Jacobs v. Payward, Inc. D. Connecticut (USA) 30 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Admonishment
Yves Hector Vimegnon v. Gallagher Bassett Services, Inc. D. Oregon (USA) 30 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Nicole Olbera, et al. v. Tiara Sykes CA Indiana (USA) 30 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Edward Reynolds v. Progressive Technologies, Inc. W.D. Tennessee (USA) 30 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Megan E. Bryan v. Child Support Enforcement Agency, State of Hawaiʻi SC Hawaiʻi (USA) 30 March 2026 Pro Se Litigant Implied
Fabricated Case Law (2)
Warning
Shaun Fleck v. Del-One Federal Credit Union D. Oregon (USA) 30 March 2026 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Warning
76 Route 6 Holdings Inc. v. Town of Yorktown, NY S.D. New York (USA) 30 March 2026 Lawyer Implied
False Quotes Case Law (2)
Admonishment
Beedemariam Kassaw v. Wal-Mart Corporation W.D. New York (USA) 30 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Brief Struck
(Ezequiel Cunha de Moura e outro v. Wallace de Moura Silva TJ-RJ (Brazil) 30 March 2026 Lawyer Implied
Fabricated Case Law (1)
Bar Referral
Amtrust North America o/b/o Justin McGinness v. Liberty Mutual Insurance Company SC New Jersey (USA) 27 March 2026 Lawyer Implied
Fabricated Case Law (4)
Monetary Sanction; Adverse Costs; CLE (recommended) 9000 USD
Source: Robert Freund
McCarthy v. U.S. Drug Enforcement Administration CA Third Circuit (USA) 27 March 2026 Lawyer Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Reprimand; Notification to other courts and the National Disciplinary Data Bank
Source: Robert Freund
Andrea K. Tantaros v. Fox News Network, LLC, et al. S.D. New York (USA) 27 March 2026 Pro Se Litigant Implied
Fabricated Case Law (7), Legal Norm (2)
False Quotes Case Law (1)
Warning
Source: Volokh
Pizzimenti v. City of Detroit, et al. E.D. Michigan (USA) 27 March 2026 Pro Se Litigant Implied
Fabricated Case Law (3)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Warning
William C. Maxwell v. Dakota Michael & Chelsey Smith S.D. Indiana (USA) 26 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Referral to Magistrate
Report
Plaintiff's Rebuttal
Anthony Wallace v. PennyMac Loan Services, LLC, et al. D. Nevada (USA) 26 March 2026 Pro Se Litigant Implied
Fabricated Case Law (5)
False Quotes Case Law (2)
Warning
Source: Jesse Schaefer
Mission Critical Project Services, Inc. GAO (USA) 26 March 2026 Lawyer Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Warning
Source: David Timm
The Advocates for Human Rights and L.H.M. v. U.S. Department of Homeland Security, et al. D. Minnesota (USA) 26 March 2026 Implied
False Quotes Case Law (1)
Report
ICE's Memorandum in Opposition
Coomer v. Lindell/MyPillow, Inc. (2) D. Colorado (USA) 25 March 2026 Lawyer Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Show Cause Order
Elilton Alves Gouveia v. Meridian Financial Investments CA Florida (4th) (USA) 25 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (4)
Warning (and a limerick)

The limerick in question:


"There once was a litigant pro se,

Who let an AI lead the way.

It briefed every claim,

Cited cases—by name,

That vanished by morning’s next day."

Hong Chris Lu v. Capital One, N.A., et al. N.D. Ohio (USA) 25 March 2026 Pro Se Litigant Implied
Fabricated Case Law (2)
Factor in dismissing the case with prejudice
Fecteau v. Safety National Casualty Corporation S.D. New York (USA) 25 March 2026 Pro Se Litigant Implied
Fabricated Legal Norm (1)
False Quotes Case Law (1)
Source: Jesse Schaefer
Michael A. DeVita v. Midtown Motors, et al. M.D. Alabama (USA) 25 March 2026 Pro Se Litigant Implied
Fabricated Case Law (3)
Case dismissed without prejudice
Kevin Lee Biglow v. Dell Technologies Inc. CA Tenth Circuit (USA) 24 March 2026 Pro Se Litigant Implied
Fabricated Case Law (5)
False Quotes Case Law (1)
Warning
Segui v. Moniz D. Arizona (USA) 24 March 2026 Lawyer Implied
Fabricated Case Law (1)
Order to Show Cause
Couvrette v. Wisnovsky Oregon (USA) 23 March 2026 Lawyer Unidentified
Fabricated Case Law (1)
False Quotes Case Law (1)
Briefs struck; Monetary sanction (15.5k); Adverse costs order (94.7k); claims dismissed with prejudice 109700 USD
Report
Plaintiff's Motion for Partial Judgments

Order to show cause is here. Final judgment on costs is here.

Iyer v Nazir CA Alberta (Canada) 23 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Warning
Jane Doe, et al. v. Lincoln Consolidated Schools, et al. E.D. Michigan (USA) 23 March 2026 Lawyer Implied
Fabricated Case Law (1)
Adverse Costs Order
Stafford v. Andrew Taffet, et al. D. Oregon (USA) 23 March 2026 Pro Se Litigant Implied
Fabricated Case Law (5)
Source: Jesse Schaefer
Gregory Hardy v. K. Jones, et al. E.D. Michigan (USA) 23 March 2026 Pro Se Litigant Unidentified
False Quotes Case Law (2)
Warning
Source: Jesse Schaefer
Nicholas and Barbara Moulder v. Davis School District (on behalf of M.M.) D. Utah (USA) 23 March 2026 Lawyer Unidentified
Fabricated Case Law (2)
False Quotes Case Law (1)
CLE; Monetary Sanction 1525 USD
Source: Jesse Schaefer
Ben-Cohen v. Municipality of Ramat Gan Supreme Court (Israel) 22 March 2026 Lawyer Implied
Fabricated Case Law (4), Legal Norm (1)
Adverse Costs Order 30000 ILS

The municipality relied on non-existent legal authorities (an invented Ministry of Education Director-General Circular and several fabricated or incorrectly quoted court decisions) in its reply to the appellant and in court pleadings. The Supreme Court found these to be the product of uncontrolled AI use, accepted the appeal on that basis and ordered costs of 30,000 ILS against the municipality.

Kibbutz Beit Nir v. Ronen Marciano National Labor Court (Israel) 22 March 2026 Lawyer Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Monetary Penalty 2500 ILS
Prososki v. Regan Nebraska SC (USA) 20 March 2026 Lawyer Implied
Fabricated Case Law (2)
False Quotes Case Law (1), Legal Norm (1)
Misrepresented Case Law (1)
Appellant's brief stricken; appellant's appeal dismissed; Bar referral
Hessert v. Hessert & Wieland-Pulayya CA Florida (6th) (USA) 20 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Order to show Cause
Dominique Lopez v. Mead Johnson Nutrition Company N.D. California (USA) 20 March 2026 Lawyer Implied
False Quotes Case Law (1)
Order to Show Cause
Daniel Gentry v. Calvin Thompson et al. E.D. Louisiana (USA) 20 March 2026 Lawyer ChatGPT
Fabricated Case Law (9)
Monetary sanction & formal admonishment 1250 USD
Pamela Blair v. Sanctuary Bluff Homeowners Association, Inc., et al. CA Kentucky (USA) 20 March 2026 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)
Brief struck
State v. Coleman Ohio CA (11th) (USA) 20 March 2026 Lawyer ChatGPT
Fabricated Exhibits or Submissions (2)
Monetary Sanction; Bar Referral; Counsel disqualified in this case; Order to notify the judgment in other cases; CLE; Letter of apology 2000 USD

"{¶133} This case illustrates the peril. An attorney who, by his own counsel’s admission, was sophisticated in his understanding of AI tools permitted a non-attorney staff member to use a public generative AI platform to prepare an appellate filing. The AI tool fabricated transcript quotations—attributing specific, inflammatory statements to a real prosecutor that were never spoken. The attorney filed the document without verifying its contents. When the fabrications were identified, he did not correct the record. He appealed this court’s denial of the tainted application to the Supreme Court of Ohio without disclosing the fabrications. He proffered an AI policy that itself appeared to have been generated by AI, complete with unfilled placeholder brackets. Two months after a sanctions hearing, a filing in another court bore the unmistakable hallmarks of unchecked AI output, including a ChatGPT prompt embedded in the text of a legal brief.

{¶134} This court does not write to condemn the use of artificial intelligence in the practice of law. To the contrary, this court recognizes that AI is an inevitable and potentially beneficial feature of modern legal practice. But the use of AI does not relieve an attorney of any of the obligations imposed by the Rules of Professional Conduct, by the rules of court, or by the oath of admission to the bar. An attorney who files a document containing AI-generated content is responsible for that content, fully and without qualification. The duty to verify, the duty of candor, the duty of competence, and the duty of supervision cannot be delegated to a machine.

{¶135} The sanctions imposed herein are proportionate, individually justified, and collectively designed to serve the purposes for which the court’s sanctioning authority exists: to compensate for harm, to deter future misconduct, to protect the integrity of the judicial process, to preserve public confidence in the administration of justice, and to ensure that the practice of law remains a profession grounded in truth, accuracy, and candor. "

National Indigenous Fisheries Institute v. Canada AG Federal Court (Canada) 20 March 2026 Lawyer Implied
Fabricated Case Law (4)
Adverse Costs Order 1 CAD