Attorney/client privilegy

Have you read this? If, after having done so, you are still unclear about something, please refine your question.

Then they would be the Prosecution and not the defense.

Under certain circumstances, yes.

For example,

"... Lawyers may also breach the duty where they are defending themselves against disciplinary or legal proceedings. A client who initiates proceedings against a lawyer effectively waives rights to confidentiality. This is justified on grounds of procedural fairness - a lawyer unable to reveal information relating to the retainer would be unable to defend themselves against such actions. ..." Attorney?client privilege - Wikipedia, the free encyclopedia

What would be the circumstances?

Please do not keep asking the same question. I've merged your threads, if you have any follow-up, please respond to this thread.

As noted, Attorney/Client privilege is not absolute. But for the most part any communication directly and solely between attorney and client cannot be repeated.