Can an attorney end client-attorney confidentiality, without the clients approval?

Inspired by, but not only about, the seizure of Michael Cohen’s files.
When Cohen’s material was seized, a process was put into place to insure that nothing was given to the prosecutors that would violate attorney - client privilege. Among those items deemed confident, and there for not shared, was at least one audio tape. Recently, it has been reported that at least one of those tapes contains a conversation between Cohen and Trump concerning a potentially embarrassing if not illegal action. Rudolph Giuliani, Trump’s lawyer, has confirmed that the conversation involved payments to an alleged former mistress of Trump’s.

Now the question is, how did the New York times get that information, in order to release it? One speculation is that Trump’s team released it, so that Cohen couldn’t use the content as part of a plea bargain.

So, could an attorney (Cohen in this case), use a recording (or email or file) that is subject to client-attorney confidentiality, as part of a plea bargain? Can an attorney break confidentiality in order to same themselves? Can confidentiality be given away by the attorney, without the clients approval?

How about the reverse? Could a client release information like that, without the attorney’s approval?

Does the protection require both parties to agree to the release, or just one? And if one, which party can do it?

Earlier thread. It addresses some of your questions.

The client holds the privilege, not the attorney. The attorney doesn’t hold rights to anything. Only the client can waive it, but there are several exceptions, such as if the consultation involved furthering or committing a crime, if there was a third party present (which prevents privilege from ever being established) or other cases that the lawyer types can explain.

From Rule 4-1.6 of the Rules Regulating the Florida Bar (which are adopted from the ABA model rules and are more or less standard in most US jurisdictions):

The privilege does not attach in controversies between the lawyer and client. So if Trump files a bar complaint against Cohen, he cannot assert the privilege with regard to otherwise privileged information which Cohen wishes to offer in his own defense. He could also use it in his own defense in a civil action involving Trump (e.g. for breach of contract). The privilege also does not attach if Cohen is accused of a crime relating to his representation of Trump.

However, the privilege is case specific. The feds can’t say, “well this is no longer privileged because Cohen offered it as evidence in his own defense, so we can use it against Trump too.” Trump would have to waive the privilege himself (as he has with regard to the new porn star payoff recording).

A lawyer can end an attorney-client relationship at any time, but that just means that any interactions from that time on wouldn’t be privileged. There’s still a privilege on anything that happened before that.

It’s not that simple either. Even if the lawyer ends the attorney-client relationship, communications made with a lawyer for the purpose of obtaining legal advice are privileged. Suppose you send me an unsolicited PM here about a personal legal question. I am obligated to treat that information as privileged even if I never agree to represent or counsel you.