The Third Circuit Reprimands an Attorney Who Did Not Verify AI-Generated Case Overviews a Non-Attorney Had Given Him

The US Court of Appeals for the Third Circuit filed a precedential opinion on March 27, 2026 in a matter that grew out of an appeal against the Drug Enforcement Administration. An attorney submitted a brief that "contained legal authority summarized and provided to him by a non-attorney," and "failed to verify the legal authority in any way." The court imposed a reprimand. One judge, concurring in part and dissenting in part, would have imposed more severe sanctions. Parts of the opinion follow, not the whole, and the attorney it names is not named here.

Background

To argue that the agency had acted inconsistently with its prior practice, the opening brief summarized eight of the agency's adjudications. In preparing those summaries, the court says, the attorney "relied on case overviews generated by AI and provided to him by a non-attorney." The attorney "modified some of the [provided] language for ease of reading and then simply incorporated the same into the brief" without verifying the citations, and signed it as an officer of the court.

"The summaries for seven of the authorities were riddled with factual and legal inaccuracies, and one of the authorities simply did not exist." The government's response brief cataloged the failures. The attorney read it and still did not check the citations. The reply brief, filed on February 6, 2025, said the erroneous citations were part of "a good faith effort to chronicle Agency disparities," and called the inaccuracies "immaterial misstatements" and "minor discrepancies."

By the attorney's own account, AI use was first suspected in early February 2025 and confirmed in mid-February. Then, the court says, "Attorney took no action whatsoever." Only when the court ordered copies of the eight adjudications, on May 15, 2025, did the attorney check them. That was "the first time" the inaccuracies, and the authority "hallucinated by AI," were disclosed.

The Violation and the Sanction

The majority did not find a breach of the duty of candor to the court. That rule, in the Pennsylvania Rules of Professional Conduct to which the attorney is subject, is broken only when a false statement of material fact or law is made "knowingly," and the court found it "debatable" whether the attorney knew the summaries were false. Of the reply brief's claim of "good faith," the court says the attorney likely knew it was false, but "the false statement must be one of a material fact," and in answering the agency's argument the attorney's good faith was immaterial. It did find a breach of the duty of competence, which requires "the legal knowledge, skill, thoroughness and preparation reasonably necessary for the representation."

"In the first instance, competent representation required that Attorney be so thorough as to check all the citations in his Opening Brief before signing and filing it," the court says. This is especially so, it says, given that the legal authorities and their substance were provided by a non-attorney.

The sanction was a reprimand, and the clerk will notify the other courts where the attorney is admitted and the National Disciplinary Data Bank. The court counts as mitigating that it had not yet addressed "the failure of attorneys to use AI with appropriate guardrails." Without that, and had the attorney been told the competence rule was in question, "it is likely that monetary sanctions would have been imposed here." The court adds that "As this precedent has now been set, the first mitigating factor will not apply in the future," and that violators "may well face any of the sanctions available."

Mistakes Do Happen

The court says its decision is neither a critique nor a comment upon the attorney's reliance on others in conducting research, nor upon the "use of AI generally." "With proper supervision and vetting, both may be helpful to an attorney. Nor are perfect summaries and citations needed to avoid sanctions. Mistakes do happen."

What drew the sanction, it says, was "Attorney's overall conduct over the course of months." Had the attorney checked the citations on receiving the government's brief and told the court, "our decision today would be different." Had the attorney taken reasonable efforts to ensure the reliability of the opening brief in the first place, "we would not be here at all."

The judge who dissented in part reads the duty of candor differently. In that judge's view the attorney broke it at least twice, and "The sanctionable conduct is not merely Attorney's filing of a brief with incorrect and hallucinated citations, but also his subsequent actions, inactions, and lack of candor that continued until he was eventually held accountable by this Court."

All three judges found a failure of competence, and one found a failure of candor too. Both readings begin with the same check, left undone before the brief was filed.