3M Loses $61.5 Million Lawsuit After Expert Witness Relies on ChatGPT
St. Paul, Monday, 17 August 2026.
An expert witness used ChatGPT to generate a biased defense report for 3M, leading to a $61.5 million jury verdict and exposing major legal risks in AI automation.
Verdict and AI Disclosure in 3M Litigation
A Houston jury awarded plaintiffs $61,578,273.00, rounded to $61.5 million, in a wrongful death lawsuit against 3M (NYSE: MMM) [1][2]. The verdict was received on Monday at 4:00 pm, aligning with the current date of 17 August 2026 [2]. The case stems from a fatal explosion at Watson Grinding in January 2020, which killed three people and destroyed approximately 200 homes [1]. Legal scrutiny intensified after it was revealed that an expert witness defending 3M used ChatGPT to generate significant portions of his defense report [1]. The disclosure occurred during discovery when plaintiff attorney Will Moye identified a five-page document as AI-generated [1]. Discussion of the case spread across social media platforms including Bluesky and Reddit [3][4].
Expert Witness Conduct and Prompts
Josh Autenrieth of Knighthawk Engineering, hired for approximately $90,000, admitted his submitted report was 85 to 90 percent generated by ChatGPT [1]. Court filings revealed prompts instructing the AI to create an exceptional expert witness report defending the standard of care at 3M [1]. Autenrieth also used the tool to analyze gas detector images and grade his own report, which received a score of 97 out of 100 from the AI [1]. Plaintiff attorney Will Moye stated that the expert relied on AI exclusively to form his opinions rather than as an assistive device [2]. Autenrieth claimed he used the tool to jog his memory while sitting in traffic [1].
Financial Impact and Legal Precedent
This verdict adds to previous related judgments totaling 156 million against the involved parties [1][2]. The jury assigned the remaining 70% of liability to Watson Grinding in the current case [1]. International precedents regarding AI-generated evidence have shown skepticism, with a Canadian judge previously ruling to place no weight on such evidence [1]. The outcome highlights growing corporate governance risks as courts scrutinize reliance on unverified automation in high-stakes litigation [1]. 3M faces continued litigation with additional cases related to the explosion pending status checks [1].