From Judge Anne Traum (D. Nev.) Monday in Villanueva v. Las Vegas Metro. Police Dep't (the underlying lawsuit alleges a jail corrections officer abused plaintiff when plaintiff was arrested):
Plaintiff Jose Villanueva sued Defendants Francis Soriano and the Las Vegas Metropolitan Police Department ("LVMPD"), for violations of state and federal law that occurred while he was detained at Clark County Detention Center ("CCDC")….
Plaintiff's expert witness, Tom Melton, testified in his October 1, 2025 deposition that he relied upon ChatGPT, an artificial intelligence program, to assist him with researching and drafting his expert report…. Defendants filed a motion to compel the production of Plaintiff's expert Tom Melton's ChatGPT history log with respect to his preparation of his expert report….
A party or its "representative" may invoke the trial preparation privilege to shield against the discovery of "documents and tangible things that are prepared in anticipation of litigation or for trial." Fed. R. Civ. P. 26(b)(3)(A). Subject to Rule 26(b)(4) and upon a threshold showing of discoverability, "substantial need," and "undue hardship," trial preparation documents may be subject to discovery. However, any court-ordered production of trial preparation materials must be structured to "protect against disclosure of the mental impressions, conclusions, opinions, or legal theories of a party's attorney or other representative."
Expert witnesses may also invoke discovery privileges related to their draft reports. In their expert report, expert witnesses are required to include "the facts or data considered by the witness in forming" their opinion. Rule 26(a)(2)(B)(ii) was amended in 2010 to limit disclosures to "facts or data considered," instead of previous language on "data or other information" that was interpreted by many courts as requiring the disclosure of "all attorney-expert communications and draft reports." The rules distinguish between the required disclosure of facts or data considered, and an expert's drafts of their report, which are protected from discovery….
The court held that parts of the history log had to be disclosed:
