Hill v. Workday

Anthony C. Hill v. Workday, Inc., United States District Court for the Northern District of California, September 5, 2025, No. 23-cv-06558-PHK, Doc. 161 (Order re: Response to Order to Show Cause by Attorneys Webb and Cervantes). Copy of primary document: ~/workspace/goals/ai-sanctions-case-monitoring/files/sources/D-83-hill-v-workday.pdf

Attorney Katherine Cervantes used Westlaw's CoCounsel, an AI research tool, to help draft her client's portion of a joint discovery letter brief and failed to verify a fabricated citation to nonexistent law. The court found a breakdown and failure to check or even try to read the cited law. Attorney Lenden Webb, also counsel of record, did not file a separate response to the order to show cause and did not appear at the hearing.

The court admonished and sanctioned Cervantes for the fake citation. It ordered her to circulate the order, the order to show cause, and her response to all attorneys and paralegals in her office; and to complete four hours of live continuing legal education approved by the California State Bar (at least one hour on law practice management and supervision of staff, one hour on professional responsibility and ethics, and one hour on the ethical and professional use of AI and large language models), filing proof of completion. The court separately ordered Webb to file a one-page response, leaving his show-cause matter pending. By follow-on order (Doc. 230, filed April 28, 2026), the court admonished Webb and imposed a personal sanction of $1,001, payable by May 22, 2026 and not by his firm, together with circulation of the orders and his responses to all firm attorneys and paralegals, distribution of his CLE materials to the firm, and four hours of live in-person CLE within six months (at least two hours on supervision and two on the ethical and professional use of AI).

Treat AI research tools as citation generators that require human verification, not as verified sources. Read the cited law itself before relying on it, especially when the tool is newly adopted at the firm.