Sullivan & Cromwell Apologizes for AI-Generated Fake Citations in Bankruptcy Court Filing
Sullivan & Cromwell, one of Wall Street's most prestigious law firms, has apologized to a federal bankruptcy judge for submitting a court filing riddled with fabricated legal citations and other errors generated by artificial intelligence. The 140-year-old firm, which represents the bankrupt company Prince Global Holdings, discovered the mistakes after a rival law firm flagged them during proceedings in U.S. Bankruptcy Court for the Southern District of New York.
Partner Andrew Dietderich sent an apology letter to Chief Judge Martin Glenn on April 18, acknowledging that the firm's motion contained what he described as AI "hallucinations"—instances where artificial intelligence tools fabricated case citations, misquoted legal authorities, and generated non-existent sources. The errors were so extensive that Dietderich's letter included a three-page attachment, single-spaced, cataloging the inaccuracies. Sullivan & Cromwell subsequently filed a corrected motion with redlined changes showing entire sentences and citation strings that had been removed or replaced.
The incident is particularly notable because it involved a firm with comprehensive internal policies governing AI use and a secondary review process designed to catch exactly this type of error. Dietderich acknowledged that both safeguards failed in this case, stating that firm policies were not followed and the citation review process was ineffective. He noted that opposing counsel at Boies Schiller Flexner, representing creditors in the case, had actually identified the hallucinations and brought them to the firm's attention, leading to the apology and corrected filing.
The Sullivan & Cromwell incident underscores a broader crisis in the legal profession. According to legal researchers tracking AI errors, fake legal citations have become increasingly common since 2023, with more than 330 court filings now documented as containing AI-related inaccuracies. Some judges have begun imposing sanctions in cases where such errors appear, raising the stakes for law firms experimenting with AI tools in high-stakes legal work. Sullivan & Cromwell said it is now evaluating enhancements to its training protocols and review procedures to prevent similar failures in the future.