Nippon Life Insurance Company sued OpenAI after ChatGPT allegedly acted as a de facto lawyer for Graciela Dela Torre, an Illinois disability claimant who had already settled her case. When her real attorney told her the settlement couldn't be reopened, she asked ChatGPT if she'd been "gaslighted." The chatbot told her to fire her lawyer, helped her draft over 60 pro se filings across two federal cases, and produced fabricated case citations including an entirely invented case called "Carr v." something. Nippon is suing OpenAI for unauthorized practice of law under Illinois state law, arguing it spent huge amounts of time and money dealing with AI-generated litigation that should never have existed.

India's Supreme Court stayed a property-dispute ruling after discovering the trial court judge had relied on non-existent, AI-generated case citations. An Andhra Pradesh junior civil judge admitted using an AI tool for the first time without verifying the outputs. The Supreme Court termed the reliance on fabricated judgments as "misconduct" with "a direct bearing on the integrity of the adjudicatory process." Separately, the Bombay High Court fined a litigant 50,000 rupees for filing AI-generated submissions citing the non-existent case "Jyoti vs. Elegant Associates." The Chief Justice flagged an "alarming trend" of AI-fabricated judgments including one titled "Mercy vs Mankind."

The U.S. Court of Appeals for the Fifth Circuit sanctioned attorney Heather Hersh $2,500 after finding her brief contained 16 fabricated quotations and five additional serious misrepresentations of law or fact, all apparently AI-generated. The court expressed frustration that AI-hallucinated legal citations "have increasingly become an even greater problem in our courts" and that the issue "shows no sign of abating." Hersh initially denied using AI, then shifted to claiming she "relied on publicly available versions of the cases, which she believed were accurate."

Maryland attorney Kusmin Amarsingh used ChatGPT to draft her appellate brief against Frontier Airlines without verifying any citations, resulting in multiple nonexistent cases being cited in the 10th Circuit. The court found her conduct "reckless" for completely failing to perform "an attorney's fundamental duty to the court." She was fined $1,000 and referred to Maryland attorney-disciplinary authorities.

Attorney Steven Feldman filed multiple motions containing AI-fabricated case citations in Flycatcher Corp. v. Affable Avenue LLC. Despite explicit court warnings and access to Westlaw and Lexis, he continued submitting unverified AI output -- even using AI to draft his response to the court's show-cause order, which contained yet more fake citations. Judge Failla imposed the most severe AI-hallucination sanction yet: default judgment against his client.

A federal judge in the District of Kansas fined four attorneys a combined $12,000 for court filings containing AI-generated fabricated legal citations in a patent infringement case. The attorney who used ChatGPT received $5,000; two who failed to review the filings received $3,000 each; local counsel who did not identify errors received $1,000. The judge called the volume of fabricated case law "staggering."

Attorneys Yen-Yi Anderson and Jeffrey Goldin jointly filed a motion in Lifetime Well v. IBSpot containing at least eight AI-generated false citations. Judge Kearney imposed differential sanctions based on their responses: Anderson, who blamed time pressure and fired her law clerk rather than accepting responsibility, received $4,000 in monetary sanctions. Goldin, who promptly accepted responsibility and implemented remedial measures, received no monetary penalty.

A New York appellate court imposed $10,000 in sanctions after a lawyer submitted briefings in a mortgage foreclosure case containing fabricated case citations identified as likely AI-generated hallucinations. The court found multiple nonexistent cases and misrepresented holdings, affirming prior orders and awarding costs to the plaintiff.

Five attorneys who signed a legal brief for Lexos Media IP LLC in a patent infringement case against Overstock.com submitted fabricated case citations hallucinated by ChatGPT to a federal court in Kansas. Senior U.S. District Judge Julie Robinson issued an order requiring them to explain why they should not be sanctioned, with multiple defects attributed to AI including nonexistent lawsuits, made-up judicial quotes, and citations to real cases that held the opposite of what the brief claimed.

A federal judge in the Northern District of California sanctioned plaintiff's counsel James Dal Bon in Buchanan v. Vuori Inc. (Case 5:23-cv-01121-NC) for filing AI-generated case law citations in a motion for preliminary approval of a wage and hour class action settlement. Dal Bon used six different AI tools to prepare the memorandum, which contained hallucinated quotes and a nonexistent case citation. After the court flagged the fabricated citations, his corrected filing still contained AI-hallucinated case law. The sanctions delayed the class action settlement, ultimately converting it to an individual settlement that abandoned the class members the attorney was supposed to represent.

Los Angeles attorney Amir Mostafavi became the first California lawyer sanctioned for AI-generated legal fabrications when a court hit him with a $10,000 fine. He ran his appeal draft through ChatGPT to improve the writing but did not verify the output before filing, unaware the tool had inserted fabricated case citations.

Gordon Rees Scully Mansukhani, one of the largest U.S. law firms, was caught filing AI-hallucinated case citations in an Alabama bankruptcy proceeding. An associate initially denied using AI under oath before the firm acknowledged the fabricated references and paid over $55,000 in sanctions and fees. Months later in February 2026, the same firm was reported to have filed a second brief containing hallucinated citations in a separate matter, making it the first Am Law 100 firm known to be a repeat offender.

In Mata v. Avianca (S.D.N.Y.), plaintiff Roberto Mata sued the airline after a metal serving cart struck his knee during a 2019 flight. His attorney Peter LoDuca filed a brief opposing dismissal that cited six judicial decisions. When opposing counsel and the court couldn't locate any of the cited cases, Judge Kevin Castel demanded copies. It turned out attorney Steven Schwartz at the same firm had used ChatGPT to research and draft the brief, and the AI had fabricated every case, complete with fake quotes and fake internal citations. On June 22, 2023, Castel sanctioned Schwartz, LoDuca, and their firm Levidow, Levidow & Oberman with a $5,000 penalty and required them to send notices to the real judges whose names appeared in the fabricated opinions.