Massachusetts federal court revokes an out-of-state lawyer's admission and orders fees after briefs with false citations; the lawyer admitted AI drafted one
On 25 September 2026 a judge of the U.S. District Court for the District of Massachusetts granted a defence motion for sanctions under Federal Rule of Civil Procedure 11 against a California-barred lawyer admitted for one case (pro hac vice) to represent the plaintiff. The court found that an opposition the lawyer filed on 21 November 2025 was replete with inaccurate citations, including a quotation attributed to a case with a fictitious Westlaw citation, and that later oppositions cited a non-existent case. In response to the court's order to show cause, the lawyer admitted using AI to draft the first opposition and explained a belief that the enterprise-level AI software in use did not hallucinate cases. The court revoked the lawyer's pro hac vice admission and ordered the lawyer's firm to pay the defendants' reasonable fees and costs, capped at $10,000. The order does not name the AI product.
- AI system
- Unidentified AI drafting tool
- Occurred
- 21 Nov 2025
- Reported
- 25 September 2026
- Event location
- United States
- What the AI did
- Communicated with the person
- Reported harm
- Professional HarmLegal HarmFinancial Loss
- Whose AI use
- Their own AI use
- Setting
- Justice · Work
- Evidence
- AI involvement supported · Causal attribution supported · 1 source
- 5 claims: 5 documented. 4 open questions
- People reported harmed
- 1 person
AI system as recorded: An unnamed enterprise-level AI software product that the lawyer admitted using to draft a court filing, according to the sanctions order
What Happened
The filings. The plaintiff, seeking to recover a state-court judgment arising from a fatal 2019 car crash, sued insurers and rental-company entities in Massachusetts in August 2025; the case was removed to federal court and a California-barred lawyer was admitted pro hac vice. On 21 November 2025 the defendants moved to strike an amended complaint, and within five hours the lawyer filed a twenty-page opposition. The court later found that opposition replete with inaccurate citations: one case cited six times for a proposition it does not stand for, a quotation attributed to a case with a fictitious Westlaw citation, non-existent quotations and undisclosed alterations of quotations. The lawyer withdrew the opposition after the court had already ruled on the motion. Later oppositions to motions to dismiss again misused the same case, cited a non-existent case and gave a fictitious citation for a case the defendants had not cited.
The AI admission. The defendants moved for sanctions, alleging the errors resulted from the lawyer's use of AI. The court ordered the plaintiff to show cause. In the response, according to the order, the lawyer admitted using AI to draft the first opposition, explained a belief that the enterprise-level version of the AI software in use did not hallucinate cases, and said an earlier draft had been filed by mistake in haste before a vacation. The lawyer attributed the errors in the later oppositions to influenza and did not admit using AI for them. The lawyer reported adopting citation-verification procedures and completing continuing legal education on the ethical use of AI.
The ruling. The court held that there is no rule against using AI to research and draft legal papers but that it must be used responsibly, and that sanctions were warranted whether or not AI was used for the later filings. It found that continued submission of false or misleading citations after notice was not mere carelessness and showed a pattern of neglecting to check submissions. It revoked the lawyer's pro hac vice admission and ordered the lawyer's firm to pay the defendants' reasonable fees and costs, up to $10,000. Local counsel was not sanctioned. The order names no AI product.
Reported harm
According to the court's order, a lawyer who admitted using AI to draft a brief that contained fictitious citations had pro hac vice admission revoked, and the lawyer's firm was ordered to pay up to $10,000 of the defendants' fees and costs.
Outcome
ResolvedMemorandum and Order of 25 September 2026 (Dkt. 155): the defence motion for sanctions was granted and the court imposed sanctions under Rule 11. The lawyer's firm must pay the defendants' reasonable attorney's fees and costs for three sets of filings, not exceeding $10,000, with the amount to be agreed or reported to the court by 23 October 2026. The lawyer's pro hac vice admission was revoked; local counsel remains the plaintiff's counsel and was not sanctioned.
What remains unknown
- Which AI product was used and how it was prompted
- Whether AI was used for the two later oppositions, which the lawyer did not admit
- The final amount of fees and costs, to be agreed or reported to the court by 23 October 2026
- Whether the plaintiff suffered any consequence from the sanctions or the change of counsel
What the evidence supports
AI involvement: supported. The sanctions order records the lawyer's admission that an AI tool was used to draft the 21 November 2025 opposition, which the court found contained a quotation attributed to a case with a fictitious Westlaw citation and other inaccurate citations. The tool's generated draft reached the lawyer, who filed it (communicated_with); the court then sanctioned the lawyer for this and two later filings. The lawyer did not admit AI use for the later filings, and the order does not name the AI product.
5 claims: 5 documented. What the statuses mean
Documented The court found that an opposition filed on 21 November 2025 by the plaintiff's pro hac vice lawyer was replete with inaccurate citations, including a quotation attributed to a case with a fictitious Westlaw citation, and that a later opposition cited a non-existent case.
Causal attribution. The court's own findings on the filings.
- storage.courtlistener.com(opens in new tab) supports · English
'Defendants filed a Motion to Strike the Second Amended Complaint on November 21, 2025'; 'Within five hours of the Enterprise Defendants' filing of the Motion to Strike'; 'The Strike Opposition was replete with inaccurate citations, including:'; 'Attributing a quotation to a case with a fictitious Westlaw citation.'; 'Citing to a non-existent case.'
Documented According to the order, the lawyer admitted using AI to draft the first opposition, explaining a belief that the enterprise-level version of the AI software in use did not hallucinate cases, and said a prior draft had been filed by mistake.
Causal attribution. The lawyer's admission in the response to the order to show cause, as recorded by the court. It connects the AI tool's output to the fictitious citations in that filing.
- storage.courtlistener.com(opens in new tab) supports · English
'admitted to using AI to draft the Strike Opposition, explaining that he believed that'; 'the enterprise-level version of AI software he was using did not hallucinate cases'; 'a PDF version of [a] prior draft of the work product rather than the final, verified document'
Documented The lawyer did not admit using AI for the later oppositions, attributing their errors to influenza; the court held sanctions warranted whether or not AI was used for them.
Causal attribution. The court's record of the lawyer's explanation and its reasoning. The AI contribution is established only for the first opposition.
- storage.courtlistener.com(opens in new tab) supports · English
'a prolonged bout of influenza'; 'has not admitted to using AI in the Travelers and'; 'whether AI was used or not'
Documented On 25 September 2026 the court granted the defence motion for sanctions under Rule 11, revoked the lawyer's pro hac vice admission and ordered the lawyer's firm to pay the defendants' reasonable fees and costs, not exceeding $10,000; local counsel was not sanctioned.
Causal attribution. The sanctions order itself.
- storage.courtlistener.com(opens in new tab) supports · English
'is GRANTED and the Court imposes sanctions pursuant to Federal Rule of Civil Procedure 11.'; 'The Court revokes Attorney'; 'pro hac vice status'; 'These fees and costs shall not exceed $10,000.'; 'impose sanctions upon local counsel'; 'Dated: September 25, 2026'
Documented The court found that continued submission of false or misleading citations after notice was not mere carelessness and showed a pattern of neglecting to confirm the accuracy of submissions; it credited the lawyer's later citation-verification procedures and continuing legal education on the ethical use of AI.
Causal attribution. The court's findings and its account of mitigation.
- storage.courtlistener.com(opens in new tab) supports · English
'indicates that this is not an instance of mere carelessness.'; 'pattern of neglecting to confirm the accuracy of his'; 'has since implemented citation-verification procedures'; 'completed Continuing Legal Education ("CLE") credits on the ethical use of AI'
Sources
1 source inspected. Sources that repeat one account do not corroborate each other.
- U.S. District Court for the District of Massachusetts, Memorandum and Order on sanctions, Dkt. 155, case 1:25-cv-12395 (25 September 2026)(opens in new tab)
s1 · storage.courtlistener.com · Court record · English · Inspected · 25 September 2026 · Primary
How the sources were read, and where the events happened
Read in full in English by the research agent (an AI) on 2026-10-16 from CourtListener RECAP storage (HTTP 200, text extracted with pdftotext); no translation was needed. Applies to s1.
Event countries: United States. Affected-person countries: Unknown. Court countries: United States.
The filings were made in, and the sanctions imposed by, the U.S. District Court for the District of Massachusetts. Where the lawyer drafted the filings and where the lawyer lives are not used.
Reviewed for publication 2026-10-16: Published as a documented court sanction. A federal court order records a lawyer's admission that AI drafted a filing with fictitious citations, and the court revoked the lawyer's pro hac vice admission and ordered fees of up to $10,000. The lawyer, the plaintiff and the deceased are not named here.
People described
A California-barred lawyer admitted pro hac vice to represent the plaintiff in a federal civil case, whose admission was revoked and whose firm was ordered to pay up to $10,000 of the defendants' fees and costs. The lawyer is a private person and is not named here.
People reported harmed in this case
1 person
1 AI participant · 0 other people harmed
One person: the sanctioned lawyer, who admitted using the AI tool (claims c2 and c4). Local counsel was not sanctioned and is not counted. The plaintiff is not counted because the order describes no consequence of the sanctions for the plaintiff.
Counted once within this case. The same person may appear in other cases. This count does not establish AI causation.
Cite this case
Compiled per our published methodology: verification statuses, sourcing standards, and corrections process.
APA
NOPE. (2026). Massachusetts federal court revokes an out-of-state lawyer's admission and orders fees after briefs with false citations; the lawyer admitted AI drafted one. AI incidents. https://nope.net/incidents/2025-massachusetts-federal-court-sanctions-out-of-state-lawyer-who-admitted-ai-drafting-brief-with-fictitious-citations
BibTeX
@misc{2025_massachusetts_federal_court_sanctions_out_of_state_lawyer_who_admitted_ai_drafting_brief_with_fictitious_citations,
title = {Massachusetts federal court revokes an out-of-state lawyer's admission and orders fees after briefs with false citations; the lawyer admitted AI drafted one},
author = {NOPE},
year = {2026},
howpublished = {AI incidents},
url = {https://nope.net/incidents/2025-massachusetts-federal-court-sanctions-out-of-state-lawyer-who-admitted-ai-drafting-brief-with-fictitious-citations}
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