New Mexico Court Fines Lawyer $5,000, Holds Him in Contempt for ChatGPT-Fabricated Testimony in Murder Appeal

Stephen Aarons has practiced criminal defense law in New Mexico for more than 40 years. On Wednesday, the state's Supreme Court held him in contempt of court, fined him $5,000, and referred him to an attorney disciplinary board for investigation, according to the New Mexico Supreme Court's order and Reuters reporting carried by multiple outlets.

His offense: filing an appellate brief packed with fabricated witnesses and invented testimony generated by OpenAI's ChatGPT, none of which he bothered to verify before signing his name to it.

What actually happened

Aarons was hired by family members of Oscar Renee Sandoval to appeal Sandoval's murder conviction. Sandoval was sentenced to life in prison in February 2025 for killing Shiereen Al-Jibury, his partner and the mother of his children, court records cited by Ars Technica show.

In August 2025, Aarons filed a brief in that appeal. According to the New Mexico Supreme Court's order, the brief "contained false testimony from wholly fabricated witnesses" — officers named Michelle Amarillo and Sanchez, and civilians named Manal Al-Jibury and Teresa Marquez, none of whom existed in the actual trial record. The filing also invented testimony from a real witness pair, Danny and Linda Stanton, claiming they'd received threats, and attributed fictional statements about the shooter's clothing — dark pants, a white shirt — to people who never said any such thing, per the court order.

The state of New Mexico filed a motion to strike portions of the brief weeks after it was submitted. The court ordered Aarons to explain himself, and at an August 21, 2026 hearing, he did.

Aarons told the court he fed a computer-generated transcript of the trial, along with other case documents, into ChatGPT, running on OpenAI's o3 model, and assumed it would produce what he called "a bulletproof summary." He never checked it against the actual record before filing it with the court.

"It's of little comfort to know that my stupidity is what brings us together this afternoon," Aarons told the justices, according to Ars Technica.

Justice C. Shannon Bacon was not impressed. "Counsel, do you watch the news? Do you listen to the radio? Do you read anything about what's going on in the world?" Bacon asked, according to Reuters. "Because the problem with lawyers relying on AI hallucinations is an above-the-fold story."

The court's verdict

The Supreme Court's written order didn't just find negligence. It found Aarons "demonstrated a lack of remorse and a lack of concern for his client" and noted he never told Sandoval's family that the brief he filed on their behalf was riddled with fabrications until the court forced the issue.

Aarons is no longer Sandoval's attorney. The appeal is still active and was reassigned on September 2 to Kim Chavez Cook, a public defender, who declined to comment, as did the Doña Ana County district attorney's office.

In a statement to Reuters, Aarons struck a different tone than he apparently did in court. "I am remorseful but hopeful that the disciplinary board takes into account it was an honest mistake," he said. "It is a lesson learned for all professionals who rely upon this powerful but sometimes unstable technology."

Aarons' statement reflects his position: a 40-year veteran attorney says he genuinely misunderstood how badly a large language model can invent facts and that he's willing to face professional consequences for it. Whether the disciplinary board buys that as an honest mistake rather than reckless indifference is now their call.

OpenAI did not respond to a request for comment from Reuters.

Aarons is not the first lawyer to get burned this way, and he won't be the last. Dozens of attorneys nationwide have been sanctioned for filing briefs where AI invented case citations or twisted real precedent, according to Reuters. What makes this case different is that the fabrication wasn't legal citations but witness testimony in a murder appeal, the kind of error that could shape whether a man spends the rest of his life in prison based on facts nobody in the courtroom ever said.

No law licensing board has yet ruled on Aarons' future ability to practice. That referral is pending. Sandoval's actual appeal, now in the hands of a public defender, is still working through the record without the fabricated material the state moved to strike.

The technology isn't the defendant here. A lawyer signed his name to a legal document he never checked in a case where a client's freedom was on the line. The court called that out directly, and the fine and contempt finding reflect a judiciary drawing a hard line: outsourcing your job to a chatbot doesn't outsource your responsibility for what it produces.