Aguilar v. The Crawford Group, Inc.

The record

• CourtUnited States District Court, District of Massachusetts
• JudgeAngel Kelley, District Judge
• CaseNo. 25-CV-12395-AK, an action to recover a state-court judgment following a fatal car crash, removed from the Massachusetts Superior Court
• Filed25 September 2026
• SanctionedPlaintiff’s pro hac vice counsel, Blake Lindemann, and the Lindemann Law Firm. Local counsel was not sanctioned, because Lindemann admitted he alone was responsible, and was reminded of his duty to supervise pro hac vice counsel
• ToolAI, not named. Admitted for one brief, the opposition to a motion to strike. Not admitted for the two later briefs; the court held the lack of an admission “irrelevant”
• False citationsThree briefs. In the first, “approximately half of the citations” contained an error, including a fictitious Westlaw citation and one case cited six times for a proposition it does not contain. The later briefs cited a case that does not appear to exist, misattributed quotations and gave wrong citations
• AmountReasonable attorney’s fees and costs of the defendants who moved, for three pieces of work, which “shall not exceed $10,000”. The parties must file a joint notice of the agreed amount, or of their dispute, by 23 October 2026
• AdmissionPro hac vice status revoked. Local counsel remains counsel of record; status conference 9 November 2026
• AuthorityFederal Rule of Civil Procedure 11, on the defendants’ motion and on the court’s own initiative. The court did not reach its inherent authority or 28 U.S.C. § 1927
• DisciplineNo referral ordered

What the court found

The first brief was filed less than five hours after the motion it answered, though counsel had two weeks. He withdrew it six days after the court had already ruled on the motion, with a one-line notice that did not say the brief contained fictitious citations. By then Rule 11’s safe harbour was closed: once a court has ruled on a filing, it can no longer be withdrawn to avoid sanctions.

His explanations did not persuade the court. He said an earlier draft PDF had been filed by mistake in the haste before a vacation, but “Lindemann has never submitted the correct draft”. He attributed the errors in the later briefs to influenza, but he had already been granted an extension for the illness and did not ask for another. For five months, the court said, he “obfuscated”, and the first admission of careless conduct came only in his response to the court’s order to show cause.

“There is no rule against the use of AI in researching and drafting legal papers, but it must be utilized responsibly. The use of AI does not diminish an attorney’s professional and ethical obligations under Rule 11.”

What turned carelessness into a pattern was notice. The later briefs contained citation errors even though they were filed after the defendants had emailed him about the first brief and after the motion for sanctions was filed. The court held that “Lindemann’s continued submission of briefing containing false or misleading citations, even after receiving notice, indicates that this is not an instance of mere carelessness.” Bad faith was not required: the court quoted the First Circuit, “a pure heart no longer excuses an empty head.”

The court recognised his later steps, citation-verification procedures and continuing legal education on the ethical use of AI, and held that they “do not detract from the need to deter Lindemann and other attorneys from irresponsibly using AI without confirming their work.” It set out the range of sanctions courts now use, from monetary penalties, fee awards and bar referral to continuing education, notice to the client, revocation of admission and dismissal, and chose a fee award and revocation.

Why it matters

Three features travel. First, the tier of the tool is no defence. A lawyer’s belief that a paid, enterprise-grade AI product does not invent cases is now on the record, and rejected. Wadsworth v. Walmart, where the citations came from a firm’s own in-house platform, made the same point from the other side and is cited in this order for the revocation of pro hac vice admission.

Second, the duty is the checking, not the tool. The court sanctioned all three briefs, including the two where AI use was never admitted: “whether AI was used or not”, the citations were not confirmed.

Third, notice escalates. The first brief was a failure to check. The briefs filed after the warning were treated as a pattern, and the pattern cost counsel his admission to the court.

Sources

• Aguilar v. The Crawford Group, Inc., No. 25-CV-12395-AK (D. Mass. Sept. 25, 2026), Memorandum and Order on Motion for Sanctions, Doc. 155, nineteen pages, the copy read in full for this page, from Damien Charlotin’s AI Hallucination Cases document store

Related

• The full sanctions record
• Wadsworth v. Walmart, a firm’s in-house AI platform and a pro hac vice revocation, cited in this order
• Mata v. Avianca, also cited in this order
• State ex rel. Schnell v. Richardson, where the court said in terms that it was not sanctioning the AI use
• Verification is becoming a duty. Evidence of verification is the missing layer.

Verified 26 September 2026 against the order, read in full. The final amount of fees and costs is not yet fixed. Information, not legal advice.