AI hallucinated — and now an elite law firm is profusely apologizing to a federal judge

An apology has been issued by a partner at the prestigious Wall Street law firm Sullivan & Cromwell for inaccuracies found in a court document, notably attributed to AI hallucinations. Andrew Dietderich, co-head of the firm's Global Finance & Restructuring division, expressed regret in a letter dated April 18, acknowledging that the previous filing included erroneous citations and other mistakes, specifically noting the occurrence of AI-generated inaccuracies. In his letter, Dietderich explained that 'hallucinations' refer to instances where artificial intelligence tools create fictitious case citations, misrepresent legal authorities, or even invent nonexistent legal references. He stated, "We deeply regret that this has occurred." The accompanying chart detailed the incorrect case names and numbers, alongside fabricated quotes from legal cases. The errors were initially identified by the law firm Boies Schiller Flexner, which represented creditors in the case involving the bankrupt Prince Global Holdings. Dietderich expressed gratitude to them for their diligence and extended his apologies. Despite Sullivan & Cromwell's long-standing reputation, with over 1,000 attorneys and 140 years of history, Dietderich emphasized that the firm's stringent AI usage policies were not adhered to, leading to these oversights. He communicated to Chief Judge Martin Glenn, based in Manhattan, that both he and the firm recognize their duty to maintain accuracy in all legal submissions. "I take responsibility for the failure to do so," he stated, and assured that a revised version of the filing would be submitted. Neither Dietderich nor a representative for Sullivan & Cromwell responded to requests for comments from Business Insider, and the judge's representative also remained silent. The phenomenon of AI hallucinations is not unique to Sullivan & Cromwell; legal researcher Damien Charlotin has noted an increase in fake legal citations since 2023, maintaining a public database that tracks such occurrences in legal cases.