New Mexico Court Sanctions Attorney Over AI-Generated Brief Citing Fabricated Witnesses

The New Mexico Supreme Court has held attorney Stephen Aarons in direct contempt of court after he filed a legal brief generated with ChatGPT that contained fabricated testimony from witnesses who do not exist, according to an order issued Wednesday.

The state’s highest court found that the brief included “false testimony from wholly fabricated witnesses,” among them invented police statements, alongside other errors. In addition to the contempt finding, the court referred Aarons to a disciplinary board for further proceedings, concluding that he “demonstrated a lack of remorse and a lack of concern for his client.”

According to the court’s order, Aarons acknowledged that he did not verify the factual claims or legal authorities in the AI-assisted brief before signing and filing it. He also admitted that he never told his client about the failure, or about the multiple factual and legal misrepresentations contained in the filing.

Aarons, a criminal defense lawyer who has practiced in New Mexico for more than four decades, was retained by family members of a defendant to pursue an appeal of a murder conviction. His client, Oscar Renee Sandoval, received a life sentence in February 2025 following his conviction for the killing of Shiereen Al-Jibury, his partner and the mother of his children.

AI hallucinations in the courtroom

The case adds to a growing list of incidents in which generative AI tools have produced convincing but false citations or testimony that made their way into official legal filings. Courts across the United States have increasingly warned attorneys that using AI drafting tools does not relieve them of their professional obligation to verify every factual assertion and legal authority they submit.

Unlike sanctions involving purely fictional case citations, this matter involved invented witness testimony in a real criminal appeal, raising the stakes for both the attorney and his client.

Market snapshot

In adjacent legal-tech and software markets, investors continued to track application software names. PDF Solutions (PDFS), which provides software and services for integrated circuit design analytics, traded at $47.15, down 1.44% from its previous close of $47.84, giving the company a market capitalization of roughly $1.99 billion.

What to watch

• Outcomes of the disciplinary board proceedings following the Supreme Court’s referral.
• Whether the New Mexico Supreme Court or state bar issues formal guidance on attorney use of generative AI tools.
• Any additional court rulings addressing fabricated AI content in legal filings, which have become an emerging pattern across jurisdictions.

Source: original release