Privileged Or Public? How Use Of AI Can Undermine The Attorney-Client Privilege

Use of public generative artificial intelligence (GAI) models like ChatGPT, Claude, and Google Gemini by lawyers and their clients has long carried privacy concerns. For the most part, those concerns were theoretical. They did not meaningfully deter attorneys seeking efficiency or clients attempting to reduce costs by posing legal questions directly to AI tools. That theoretical risk has now become real.

In U.S. v. Heppner, decided in February 2026, the United States District Court for the Southern District of New York addressed what it described as a "question of first impression nationwide": whether a criminal defendant waived the attorney-client privilege and/or the attorney work product doctrine when he interacted with a GAI platform regarding his defense strategy. The court ruled that he did, because his attorney had not directed Heppner's use of the GAI platform, and because Heppner had no reasonable expectation of privacy in his interactions with the GAI platform, and