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 (7 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.

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Last updated: 20 April 2026
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)
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)
Attorney Disciplinary Board v. Richard Louis Pazdernik, Jr. Iowa Supreme Court (USA) 31 October 2025 Lawyer ChatGPT
Fabricated Case Law (1)
Misrepresented Case Law (1)
Public reprimand
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
Turner v. Garrels CA Iowa (USA) 4 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Source: Jesse Schaefer
April Ann Nelson v. Navient Solutions, LLC, et al. S.D. Iowa (USA) 4 September 2025 Pro Se Litigant Implied
Fabricated Case Law (3)
Warning
Source: Jesse Schaefer
Luke v. Iowa DHHS CA Iowa (USA) 6 August 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
in re: Turner Iowa Attorney Disciplinary Board (USA) 9 July 2025 Lawyer Implied
Fabricated Case Law (1)
Motion stricken