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 (73 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)
Jenson & Lockridge (No 2) Federal Circuit and Family Court (Australia) 19 March 2026 Pro Se Litigant Unidentified
Misrepresented Doctrinal Work (1), Exhibits or Submissions (1), other (1)
Adverse Costs Order; Appeal dismissed 1540 AUD
Edmonds v Barrington Winstanley Group SC New South Wales (Australia) 18 March 2026 Lawyer Implied
Fabricated Case Law (1), Exhibits or Submissions (1)
Warning
GSA v. Department of Communities SC Western Australia (Australia) 16 March 2026 Pro Se Litigant Unidentified
False Quotes Legal Norm (1)
Nicole Levey-Wilson v The Trustee for Attivita Group Unit Trust Fair Work Commission (Australia) 10 March 2026 Pro Se Litigant Implied
Misrepresented Legal Norm (1)
Application dismissed.
Malik v Insurance Australia Limited D. New South Wales (Australia) 6 March 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
False Quotes Exhibits or Submissions (1)
Adverse Costs Order
⚠ Alleged AI Use
Oberoi v. Douglas CA Victoria (Australia) 5 March 2026 Lawyer Implied
Fabricated Case Law (1)
False Quotes Case Law (1)
Bar referral
ELG20 v Minister for Immigration and Citizenship Federal Circuit and Family Court (Australia) 5 March 2026 Pro Se Litigant ChatGPT; OpenAI
Fabricated Case Law (1)
False Quotes Case Law (1)
Admonishment
Rinaldi v Department of Justice (Right to Information and Privacy) Queensland CAT (Australia) 16 February 2026 Pro Se Litigant Implied
Fabricated Case Law (2)
Appeal dismissed
RYJZ and Commissioner of Taxation (Taxation) ART Australia (Australia) 12 February 2026 Pro Se Litigant Implied
Fabricated Case Law (2)
Morcos v Bayside Council IRC New South Wales (Australia) 10 February 2026 Pro Se Litigant Implied
Fabricated Case Law (2)
Jorgensen v JML Rose Pty Ltd (Security for Costs) Federal Court of Australia (Australia) 9 February 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Order for security for costs
Application by Pennisi Fair Work Commission (Australia) 5 February 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Pasuengos v Minister for Immigration and Citizenship (No 2) Federal Circuit and Family Court (Australia) 3 February 2026 Lawyer Unidentified
Fabricated Case Law (3)
Bar Referral
Broadwater Tower Queensland BCCMC (Australia) 2 February 2026 Pro Se Litigant Implied
Fabricated Legal Norm (3)
Warning
Health Care Complaints Commission v Campbell NSW CAT (Australia) 30 January 2026 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (2)
Outdated Advice Repealed Law (1)
Riley v. Nuvei Australia Merchant Services Fair Work Commission (Australia) 19 January 2026 Pro Se Litigant Unidentified
Fabricated Case Law (2)
Lutfi v. Tucker Federal Circuit and Family Court (Australia) 16 January 2026 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Warning
Smith and Commissioner of Taxation Administrative Review Tribunal (Australia) 12 January 2026 Pro Se Litigant Implied
Fabricated Case Law (4)
Misrepresented Case Law (2)
Mrs Sandra Archer v GTC Contracting Fair Work Commission (Australia) 24 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)

The applicant's representative (Mr M Archer) cited various cases in closing submissions; the Deputy President formed the view he may have used artificial intelligence, asked him, and he admitted doing so. He was asked to supply a list of cited cases with links; the Commission stated it would disregard any cases for which citations/links could not be produced.

Tekla & Tekla Federal Circuit and Family Court (Australia) 23 December 2025 Pro Se Litigant Implied
Fabricated Case Law (3)
False Quotes Case Law (1)
Misrepresented Case Law (2)
In the matter of Bayfoyle SC New South Wales (Australia) 23 December 2025 Lawyer Implied
Fabricated Case Law (1)
Adverse Costs Order (AI misuse one of the factors); Declined to Refer to the Bar 1
Rathi & Rathi Federal Circuit and Family Court (Australia) 22 December 2025 Pro Se Litigant Implied
Fabricated Legal Norm (1)
Misrepresented Legal Norm (1)
Leytcorp v Mimbim Enterprises Trade Marks Office (Australia) 22 December 2025 Lawyer Implied
Fabricated Case Law (1)
Pasuengos v Minister for Immigration and Citizenship Federal Circuit and Family Court (Australia) 22 December 2025 Lawyer Unidentified
Fabricated Case Law (1)
Order to Show Cause

The court eventually granted some costs in a subsequent decision (see here).

Pakuza v Workers' Compensation Regulator Queensland IRC (Australia) 16 December 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Chu v Darmali FCA (Australia) 8 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Misrepresented Exhibits or Submissions (1)
Outdated Advice Overturned Case Law (1)
Carrington v TAFE Queensland Queensland IRC (Australia) 5 December 2025 Lawyer Implied
Fabricated Case Law (2)
A'Vard v Mornington Peninsula SC Victorian CAT (Australia) 2 December 2025 Pro Se Litigant Unidentified
Fabricated Case Law (2)
Mertz & Mertz (No 3) Family Court (Australia) 28 November 2025 Lawyer Unidentified
Fabricated Case Law (1)
Costs Order; Bar Referrals 10000 AUD
Re Walker SC Victoria (Australia) 24 November 2025 Lawyer CourtAid; ChatGPT
Fabricated Case Law (1)
Misrepresented Case Law (1)
Reprimand
Kim v. Insurance Australia ACT CAT (Australia) 18 November 2025 Judge Bard
Fabricated Case Law (2)
Decision was removed from ACAT website

Misuse of generative AI was later confirmed by the registrar.

Wills v Wilson Victorian CAT (Australia) 14 November 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1), Legal Norm (1)
Clarke v State of Queensland (Department of Education) Queensland IRC (Australia) 5 November 2025 Pro Se Litigant ChatGPT
Fabricated Case Law (1), Legal Norm (1)
Huang v. Champion Homes Sales NSW (Australia) 30 October 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Misrepresented Case Law (1)

The appellant admitted using generative AI to prepare her Amended Grounds of Appeal. The Appeal Panel and respondent identified numerous incorrect or inapplicable citations and legal propositions generated by AI; the panel noted the appellant failed to verify those citations contrary to NCAT Procedural Direction 7 and treated the Amended Grounds as unreliable in parts when assessing whether questions of law were raised.

Sky Gardens Queensland BCCMC (Australia) 29 October 2025 Pro Se Litigant Implied
Fabricated Case Law (1), Exhibits or Submissions (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Adverse costs order for "misconceived and without substance" application 2000 AUD
Vivek Singha v. Metal Manufactures Fair Work Commission (Australia) 8 October 2025 Pro Se Litigant Unidentified
Fabricated Case Law (2)
Misrepresented Case Law (1)
Hugo v Affinity Education Group Pty Ltd Family Court (Australia) 18 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Warning
Howe v. NSW Department of Education NSW Industrial Relations Commission (Australia) 17 September 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (2)
Helmold & Mariya (No 2) Family Court (Australia) 12 September 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Warning

The appellant admitted using generative AI to prepare his Notice of Appeal and Summary of Argument. The Court found several cited authorities could not be located (concluding they were fictitious) and held that deploying unverified AI-generated research that cites non-existent cases breaches duties not to mislead the court and risks contravening Pt XIVB of the Family Law Act 1975 (Cth) (on confidentiality of proceedings).

Mark Khoury v Nira Kooij Supreme Court of Queensland (Australia) 3 September 2025 Pro Se Litigant implied
Fabricated Case Law (2)
Misrepresented Case Law (1), Legal Norm (1)
Application dismissed 1
Stewart v Good Shepherd Victoria CA (Australia) 29 August 2025 Pro Se Litigant Implied
Fabricated Case Law (1)
Misrepresented Case Law (1)
Gribble v Essential Energy NSW D.C. (Australia) 29 August 2025 Pro Se Litigant Unidentified
Fabricated Case Law (2)
Plaintiff ordered to exclude all Gen AI material
Butler and National Disability Insurance Agency Administrative Review Tribunal (Australia) 28 August 2025 Expert Unidentified
Fabricated Exhibits or Submissions (1)
Tribunal criticised the reliability of AI-assisted expert reports and gave them reduced weight

The Agency raised concerns that several expert reports were prepared with assistance of an artificial intelligence program and contained unverified citations and inserted text. The Tribunal noted admissions by at least one practitioner (Ms McPhee) that AI assisted drafting and found instances where citations had been corrected by another witness and where the author could not confirm whether AI added certain phrases. The Tribunal criticised the lack of independent verification and gave the reports reduced weight but did not impose sanctions.

The Meniscus Trust v Chief Commissioner of State Revenue NSW (Australia) 21 August 2025 Pro Se Litigant Google Gemini; ChatGPT Use of generative AI in submissions resulting in unverified legal citations Arguments produced by AI given lesser weight

The self-represented Applicant admitted using generative AI (Google Gemini and ChatGPT) to prepare submissions. NCAT Procedural Direction 7 requires verification of citations when Gen AI is used; the Applicant did not verify citations. The Tribunal accepted the submissions into the record but placed greater weight on primary records and noted non-compliance with the verification requirement.

JML Rose Pty Ltd v Jorgensen (No 3) Federal Court of Australia (Australia) 19 August 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1), Legal Norm (1)
False Quotes Case Law (1)
Misrepresented Case Law (1)
Outdated Advice Repealed Law (1)
N/A

""101    The use of AI technology in the Courts has been the subject of judicial observations, particularly regarding legal practitioners who are subject to professional and ethical obligations and responsibilities. However, as Bell CJ observed in May v Costaras [2025] NSWCA 178 at [15], with whom Payne JA and McHugh JA agreed, in the context of considering the use of AI in the preparation of submissions, that “(a)ll litigants are under a duty not to misled the court or their opponent.” The reliance on unverified materials produced by generative AI does have the potential to misled the Court.

102    Although the termed used in relation to erroneously generated references by AI is “hallucinations”, this is a term which seeks to legitimise the use of AI. More properly, such erroneously generated references are simply fabricated, fictional, false, fake and as such could be misleading.

103    All persons appearing before the Court have a duty to verify that the case law and legislation referred to and relied on, is accurate and that such materials actually exist. The references in Ayinde at [85] and [86] and in Costaras at [14]-[15], to matters involving litigants who are acting in person who rely on AI generated material clearly supports the position that all are required to verify the submissions made to the Court. There are many publicly available legal research websites, some which are accessible without a fee. Further, and without attempting to be exhaustive, the Queensland Supreme Court library is open and available to the public.

104    The use of generative AI to prepare submissions that may include fake authorities will nearly always introduce added costs, complexity and add to the burden of other parties and to the Court: Costaras at [16] and [49]. I gratefully adopt the observation from Ayinde at [9] that “(t)here are serious implications for the administration of justice and public confidence in the justice system if artificial intelligence is misused.” The Court in Ayinde observed from [10] to [31] the existing guidance, regulatory duties of the profession, referrals and the Court’s powers. Matters which are within the Court’s own domain include in the most serious of cases contempt of Court. The observations in Ayinde at [26]-[28] regarding contempt of court are not limited to legal practitioners.

105    As the reasons above demonstrate, the circumstances of this case involved many fake authorities, fabricated quotes and false propositions. It is unhelpful for the Court to be referred to, and for parties to rely on, such matters."

Wang v Moutidis County Court of Victoria (Australia) 18 August 2025 Pro Se Litigant Gen AI
Fabricated Case Law (2)
False Quotes Exhibits or Submissions (1)
Misrepresented Case Law (1), Exhibits or Submissions (1)
Arguments disregarded
JNE24 v Minister for Immigration and Citizenship Federal Circuit and Family Court (Australia) 15 August 2025 Lawyer Claude AI, Microsoft Copilot
Fabricated Case Law (1)
Misrepresented Case Law (1)
Referral to the Bar; Personal costs order against lawyer (who reimbursed his client) 8371 AUD
Director of Public Prosecutions v GR Supreme Court of Victoria (Australia) 14 August 2025 Lawyer Unidentified
Fabricated Case Law (2), Legal Norm (2)
False Quotes Doctrinal Work (2)
Misrepresented Case Law (1)
N/A

The court identified issues with the use of artificial intelligence in preparing written submissions. The submissions contained fabricated citations and fictitious quotes, which were initially filed as joint submissions by the defense and prosecution. Upon discovery, the defense counsel took responsibility, citing the use of AI without proper verification. The court allowed revised submissions to be filed, emphasizing the importance of accuracy in legal documents and the responsible use of AI. No professional sanctions or monetary penalties were imposed, but the court reiterated the need for adherence to guidelines on AI use in litigation.

May v Costaras NSW CA (Australia) 8 August 2025 Pro Se Litigant Unidentified
Fabricated Case Law (1)
Appeal dismissed. No specific sanction for AI use, but highlighted need for judicial vigilance.
Deysel v Electra Lift Co. Fair Work Commission (Australia) 8 August 2025 Pro Se Litigant ChatGPT
Misrepresented Legal Norm (3)
Application dismissed