Here’s a hypothetical based on an episode of LA Law I watched last night. Spoilers for a 36 year old TV show.
One patient of a psychiatrist murders another patient he had been in group sessions with. He has confessed & been convicted. The parents of the victim are suing the psychiatrist, because the murderer said he had told his plans to the psychiatrist, including showing him the machete that he planned to use.
The plaintiffs claimed that this situation created an exception to patient confidentiality, and the doctor should have told the victim and/or the police. (The doctor’s attorney was Ann Kelsey if you remember the show)
During the trial, the convicted murderer testifies. During the testimony, Ms. Kelsey becomes convinced he didn’t actually do it - there are discrepancies with his previous testimony & confession, he can’t answer easy questions about the crime scene, etc. The jury finds for the defendant, at least somewhat based on doubt that the supposed murderer was actually guilty.
After the trial, Ms. Kelsey decides she needs to help the murderer get out of prison (extremely typical for her if you watch the show). She asks the doctor, her client, for assistance, including releasing notes from the group sessions to see if another patient may have been the murderer.
The doctor pulls her into a private office, confirms that they’re “still talking in the scope of the atty/client relationship”, then tells her he was the murderer. He had been having an affair with the victim, she threatened to tell his wife, and in the face of losing his career & family, he killed her. He then convinced the other patient that he had done it and should confess.
So the question - does atty/client privilege apply in that case? The case was over, the fact that he was the killer is no longer relevant, and it was a civil trial anyway. I haven’t watched the next episode yet (well, I’m sure I did 36 years ago, but whether there’s a continuation has slipped my memory).