New York / Citation decisions
Ader v Ader
Sup. Ct., New York County
2025 NY Slip Op 51563(U)
What happened
In a loan-guaranty dispute, the defendants’ opposition to summary judgment included an AI-hallucinated citation and quotations. Counsel initially described the quoted passages as intended paraphrases. The opposition to the resulting sanctions motion then added four nonexistent citations, seven nonexistent quotations and three authorities that did not support the propositions offered.
At argument, counsel acknowledged using AI and failing to verify the generated quotations. Counsel had identified one hallucinated citation during drafting and instructed colleagues to remove it, but signed the brief with that citation still present. Supreme Court, New York County, tied the failure to counsel’s own responsibility for the representations submitted to the court.
Sanction or disposition
Fees and costs on the sanctions motion and fees associated with the AI material, jointly and severally against defendants and counsel. Referral to the First Department grievance committee and the New Jersey ethics office.
From the opinion
“In the end, it is undisputed that counsel signed a brief that contained the identified hallucination among several others.”
“In sum, counsel’s duty of candor to the Court cannot be delegated to a software program.”
“If you are including citations that don’t exist, there’s only one explanation for that. It’s that AI gave you cites and you didn’t check them.”