AI Hallucination Cases

AI Use

Counsel admitted using ChatGPT to find supporting case law after failing to locate precedent manually. She cited a fictitious case (Matter of Bourguignon v. Coordinated Behavioral Health Servs., Inc., 114 A.D.3d 947 (3d Dep’t 2014)) in the reply brief, never verifying its existence.

Hallucination Details

Only one hallucinated case was cited in the reply brief: Matter of Bourguignon v. Coordinated Behavioral Health Servs., Inc., 114 A.D.3d 947 (3d Dep’t 2014). When asked to produce the case, Counsel admitted it did not exist, blaming reliance on ChatGPT.

Ruling/Sanction

The Court referred Counsel to the Second Circuit’s Grievance Panel for further investigation and possible discipline. Lee was ordered to furnish a copy of the decision (translated if necessary) to her client and to file certification of compliance.

Key Judicial Reasoning

The Court emphasized that attorneys must personally verify the existence and accuracy of all authorities cited. Rule 11 requires a reasonable inquiry, and no technological novelty excuses failing to meet that standard. The Second Circuit cited Mata v. Avianca approvingly, confirming that citing fake cases amounts to abusing the adversarial system.

AI Use

Osborne’s attorney, under time pressure, submitted reply papers heavily relying on a website or tool that used generative AI. The submission included fabricated judicial authorities presented without independent verification. No admission by the lawyer was recorded, but the court independently verified the error.

Hallucination Details

Of the six cases cited in the October 11, 2023 reply, five were found to be either fictional or materially erroneous. A basic Lexis search would have revealed the fabrications instantly. The court drew explicit comparisons to the Mata v. Avianca fiasco.

Ruling/Sanction

The court struck the offending reply papers from the record and ordered the attorney to appear for a sanctions hearing under New York’s Rule 130-1.1. Potential sanctions include financial penalties or other disciplinary measures.

Key Judicial Reasoning

The court emphasized that while the use of AI tools is not forbidden per se, attorneys must personally verify all outputs. The violation was deemed "frivolous conduct" because the lawyer falsely certified the validity of the filing. The judge stressed the dangers to the judicial system from fictional citations: wasting time, misleading parties, degrading trust in courts, and harming the profession’s reputation.

AI Use

Attorney Zachariah C. Crabill, relatively new to civil practice, used ChatGPT to research case law for a motion to set aside judgment, a task he was unfamiliar with and felt pressured to complete quickly.

Hallucination Details

Crabill included incorrect or fictitious case citations provided by ChatGPT in the motion without reading or verifying them. He realized the errors ("garbage" cases, per his texts) before the hearing but did not alert the court or withdraw the motion.

Ruling/Sanction

When questioned by the judge about inaccuracies at the hearing, Crabill falsely blamed a legal intern. He later filed an affidavit admitting his use of ChatGPT and his dishonesty, stating he "panicked" and sought to avoid embarrassment. He stipulated to violating professional duties of competence, diligence, and candor/truthfulness to the court. He received a 366-day suspension, with all but 90 days stayed upon successful completion of a two-year probationary period. This was noted as the first Colorado disciplinary action involving AI misuse.

Key Judicial Reasoning

The disciplinary ruling focused on the combination of negligence (failure to verify, violating competence and diligence) and intentional misconduct (lying to the court, violating candor). While mitigating factors (personal challenges, lack of prior discipline) were noted in the stipulated agreement, the dishonesty significantly aggravated the offense.

AI Use

The Court noted that the appellant's argument section appeared to have been drafted by AI based on telltale errors (nonexistent cases, jump-cites into wrong jurisdictions, illogical structure). A recent Texas CLE on AI usage was cited by the Court to explain the pattern.

Hallucination Details

Three fake cases cited. Brief also contained no citations to the record and was devoid of clear argumentation on the presented issues.

Ruling/Sanction

The Court declined to issue a show cause order or to refer counsel to the State Bar of Texas, despite noting similarities to Mata v. Avianca. However, it affirmed the trial court’s denial of habeas relief due to inadequate briefing, and explicitly warned about the dangers of using AI-generated content in legal submissions without human verification.

Key Judicial Reasoning

The Court held that even if AI contributed to the preparation of filings, attorneys must ensure accuracy, logical structure, and compliance with citation rules. Failure to meet these standards precludes appellate review under Tex. R. App. P. 38.1(i). Courts are not obligated to "make an appellant’s arguments for him," especially where brief defects are gross.

AI Use

The plaintiff's attorneys used ChatGPT to generate case law supporting the proposition that a body corporate can be sued for defamation. They forwarded eight cases—none of which exist—to opposing counsel during a post-hearing exchange and were unable to produce them later. Counsel admitted in open court that ChatGPT had been the source.

Hallucination Details

Fictitious cases included:

• Body Corporate of the Brampton Court v Weenen [2012] ZAGPJHC 133
• Body Corporate of Bela Vista v C & C Group Properties CC [2009] ZAGPPHC 54
• Dolphin Whisper Trading 21 (Pty) Ltd v The Body Corporate of La Mer [2015] ZAKZPHC 23
• Bingham v City View Shopping Centre Body Corporate [2013] ZAGPJHC 77
• Body Corporate of Pinewood Park v Behrens [2013] ZASCA 89
• Body Corporate of Empire Gardens v Sithole [2017] ZAGPJHC 23
• Body Corporate of the Island Club v Cosy Creations CC [2016] ZAWCHC 182
• Body Corporate of Fisherman’s Cove v Van Rooyen [2013] ZAGPHC 43

The court verified that the citations, parties, and contents were entirely fictitious.

Ruling/Sanction

The plaintiff’s entire claim was dismissed on legal grounds unrelated to the hallucinations (a body corporate cannot be sued for defamation under South African law).

Punitive costs were imposed on the attorney-and-client scale for the period between March 28 and May 22, 2023, during which the plaintiff’s legal team insisted such authorities existed. The court awarded 60% of standard costs to the defendants for the rest of the proceedings. No personal sanction or bar referral was issued due to counsel’s candor and the court's confidence that the error stemmed from “overzealous and careless” use of ChatGPT, not intent to mislead

Key Judicial Reasoning

The court stressed that AI tools like ChatGPT cannot be trusted for legal citation without human verification. Submitting hallucinated cases—even indirectly—misleads opposing counsel, wastes court time, and undermines trust in legal process. The incident was used to underscore that “good old-fashioned independent reading” remains essential in legal practice.

AI Use

Counsel from Levidow, Levidow & Oberman used ChatGPT for legal research to oppose a motion to dismiss a personal injury claim against Avianca airlines, citing difficulty accessing relevant federal precedent through their limited research subscription.

Hallucination Details

The attorneys' submission included at least six completely non-existent judicial decisions, complete with fabricated quotes and internal citations. Examples cited by the court include Varghese v. China Southern Airlines Co., Ltd., Shaboon v. Egyptair, Petersen v. Iran Air, Martinez v. Delta Airlines, Inc., Estate of Durden v. KLM Royal Dutch Airlines, and Miller v. United Airlines, Inc.. When challenged by opposing counsel and the court, the attorneys initially stood by the fake cases and even submitted purported copies of the opinions, which were also generated by ChatGPT and contained further bogus citations.

Ruling/Sanction

Judge P. Kevin Castel imposed a $5,000 monetary sanction jointly and severally on the two attorneys and their law firm. He also required them to send letters informing their client and each judge whose name was falsely used on the fabricated opinions about the situation.

Key Judicial Reasoning

Judge Castel found the attorneys acted in bad faith, emphasizing their "acts of conscious avoidance and false and misleading statements to the Court" after the issue was raised. The sanctions were imposed not merely for the initial error but for the failure in their gatekeeping roles and their decision to "double down" rather than promptly correcting the record. The opinion detailed the extensive harms caused by submitting fake opinions. This case is widely considered a landmark decision and is frequently cited in subsequent discussions and guidance.

Petitioner (an attorney) filed an amicus request accompanied by a 'fábula' co-written with ChatGPT. TSE held that amicus filings are inapplicable in electoral proceedings (Res.-TSE nº 23.478/2016), found the submission to evidence bad-faith litigation and manifestly unfounded intervention, ordered desentranhamento of the petition and imposed a monetary fine for litigância de má-fé.