Expert Witness Used ChatGPT to Write 85–90% of Report in Fatal Houston Explosion Lawsuit, Prompts Obtained via Subpoena

An expert witness hired by 3M to defend the company in a lawsuit over a 2020 Houston explosion that killed three people and destroyed roughly 200 homes used ChatGPT to draft the bulk of his expert report. Josh Autenrieth of Knighthawk Engineering, who billed at $475/hour for a total of roughly $90,000, asked the chatbot to "create an exceptional expert witness report defending the standard of care at 3M" and to "show how 3M is 0 percent at fault for the explosion at Watson Grinding." The plaintiffs' attorney discovered a five-page AI-generated "Citation Overlay" document during discovery and subpoenaed Autenrieth's full prompt history, ultimately receiving 350 pages of ChatGPT conversations, including public links to his complete chat history. Many prompts were entered the night before his deposition.

At trial, Autenrieth and opposing counsel agreed the submitted report was "90 to 85 percent ChatGPT." ChatGPT had initially declared 3M "0 percent responsible" in its draft, but advised Autenrieth to cut the line when he asked it to roleplay as opposing counsel, warning it was "an easy target." In separate exchanges, Autenrieth uploaded a photo of the gas detector at the center of the case and asked the chatbot "what am I looking at?", had ChatGPT grade his finished report (97/100), and prompted it while "sitting in traffic." 3M later moved to have Autenrieth disqualified; the plaintiffs' attorney instead called him as his own witness.