AI Might Have Hallucinated Quotations Even if You’ve Confirmed the Citations

From a Response to an Order to Show Cause in Pennantia, LLC v. Rose Cay Maritime, LLC (S.D.N.Y.), filed by lawyers from a 10-lawyer firm:

[I.] Introduction and Acknowledgment of Responsibility

Undersigned counsel acknowledge the Court’s concerns and accept full responsibility for the errors identified in Defendant’s opposition Memorandum of Law (ECF No. 32)(“Memorandum”). Specifically, the Memorandum included quotations that had not been confirmed against the cited judicial opinions prior to filing. Counsel recognize that this was a serious lapse in professional obligations under Park v. Kim, 91 F.4th 610 (2d Cir. 2024), deeply regret the error, and extend their sincere apologies to the Court, the parties, and opposing counsel.

[II.] Explanation of Circumstances

Lead counsel reviewed the cited cases in LexisNexis and confirmed that they were actual decisions relevant to the legal issues in this matter. However, the quotations included in the initial draft of the Memorandum were not independently verified against the official opinions word-for-word.

The error occurred during preparation of the Memorandum under a compressed briefing schedule in response to Plaintiff’s application for a temporary restraining order and preliminary injunction. On July 28, 2025, undersigned lead counsel used a generative artificial intelligence program to generate an initial outline addressing, among other issues, whether interest may be included in the value of a maritime lien. The draft outline contained citations to authorities, … together with purported quotations attributed to those cases. Counsel confirmed through Lexis Nexis that the cases were valid and relevant to maritime lien law, but failed to verify the accuracy of the quoted language against the official opinions.

Undersigned lead counsel departed for a previously scheduled vacation on August 2. Between July 28 and August 4, the Memorandum underwent more than eleven rounds of revisions; however, during that process the accuracy of the quotations initially generated by the AI program was never verified. Importantly, the Memorandum also cited other authorities … that supported the proposition at issue. The inclusion of the fictitious quotations was inadvertent and occurred without any purpose or intent to mislead the Court or opposing counsel.

Undersigned counsel emphasize that there was never any intent to mislead the Court or opposing counsel. The AI program was used solely as a time-saving aid in the initial drafting process. The subsequent failure to confirm the quotations was inadvertent, yet it constituted a breach of professional responsibility. Undersigned counsel fully recognize that the duty to verify authority rests squarely with the attorney in all circumstances.

[III.] Corrective Measures Implemented

Since the Court’s August 26, 2025 Order, Lennon Murphy & Phillips LLC has taken immediate and concrete steps to ensure that this type of error does not recur:

[1.] Conducted a manual review of all citations and quotations contained in Dove Cay’s submissions before this Honorable Court that resulted in the redline of Dove Cay’s Memorandum of Law (ECF No. 57-1).

[2.] All citations and quotations in any filing must now be verified directly against official sources (Lexis, Westlaw, or court websites). Attorneys must certify this verification before submission.

[3.] The firm will implement training for all attorneys regarding the proper and ethical use of generative artificial intelligence in the practice of law, with particular emphasis on Rule 11 obligations.

[4.] AI-generated text may only be used as an internal drafting aid, and only after complete, manual verification of all authorities, quotations, or other statements by the responsible attorney.

These safeguards are designed to eliminate the risk of inaccurate citations in future submissions.

The filing goes on to argue that sanctions shouldn’t be imposed, partly because “the cases cited here … are genuine, published decisions, relevant to maritime lien jurisprudence,” and “[t]he error was confined to two fictitious quotations generated by an artificial intelligence tool and mistakenly attributed to genuine cases during an expedited initial drafting process.” And the court (Judge Sidney Stein) agreed, in a Sept. 26 order:

In light of counsel’s acknowledgment of the fact that the quotations at issue were not independently verified against the actual opinions and acceptance of responsibility and the remedial measures subsequently put in place to avoid a repetition of the errors, the Court will take no further action on this matter at this time.

I think the filing made as good a case as possible for not imposing sanctions, in part because of what struck me as its candid, regretful, and professional tone.