On Sept. 12, 2025, the first California court issued an explicit “warning” to attorneys who use AI as part of their legal practice. In Sylvia Noland v. Land of the Free, L.P., et al., an otherwise unremarkable and straightforward employment-related appeal, the court discovered that much of the legal authority relied on in plaintiff’s opening and reply briefs was fabricated. The court’s published opinion aimed to address a much broader issue that has become increasingly relevant in the legal profession: the reliability and verification of legal authority generated by AI tools.
After reviewing each of the cases plaintiff’s counsel cited, the court discovered that much of the quoted language did not appear in the cited cases, certain cases cited did not discuss the topics they were meant to support, and a handful of the cases cited did not exist at all. The court determined that the AI tools plaintiff’s counsel used must have created fake legal authority—coined “AI hallucinations”—which plaintiff’s counsel failed to realize because he did not carefully review the AI’s output. The concept of AI hallucinations has been the subject of increasing discussion in federal courts and courts of other jurisdictions.
The court therefore made clear: “no brief, pleading, motion, or any other paper filed in any court should contain any citations—whether provided by generative AI or any other source—that the attorney responsible for submitting the pleading has not personally read and verified.” A failure to do so constitutes a violation of the basic duty that counsel owes to their client and to the court.
Because the court had to spend excessive time attempting to locate fabricated legal authority, which created an unnecessary burden, the court imposed a $10,000 monetary sanction on plaintiff’s counsel to be paid to the clerk of court. Further, the court ordered plaintiff’s counsel to serve a copy of the court’s opinion on his client, and the clerk to serve a copy on the California State Bar.
While AI has the potential to enhance the practice of law, and is often encouraged by many clients, attorneys must carefully heed the warning of the Court of Appeal, or risk sanctions and potential disciplinary action from the state bar. This opinion may also serve as guidance to counsel to ensure that the authority cited by opposing counsel is legitimate—and to promptly report to the court if it is not—to safeguard judicial resources.