IANAMM, but
[quote=Washington Post]
Cohen has a duty to maintain confidentiality about his interactions with Trump. Second, he’s bound by attorney-client privilege.
What’s the difference? The latter is narrower, protecting only communications between the two that’s centered on getting legal advice. Privilege is also maintained until waived by the client (here, Trump) or by a court order.
“Cohen can’t volunteer information that is either subject to this duty of confidentiality or is covered by the privilege,” Margulies said. “With respect to all that stuff, he’s obliged to keep his mouth shut, and he can discuss those matters only pursuant to a court order.”
Two asterisks that apply here. The first is one way in which attorney-client privilege can be overridden. There’s a crime-fraud exception, which removes claims of privilege from any communication aimed at furthering or covering up an illegal act. Any issues related to crimes to which Cohen has already admitted — for example, the hush-money payments — Margulies figures that congressional investigators could mandate that Cohen discuss.
The other asterisk is that only communications about legal advice are privileged.
“There’s an open question as to how much of what Cohen did was actually legal in character,” Margulies said. “You can be a fixer and do jobs for someone and happen to be a lawyer, as Cohen was. It doesn’t necessarily mean you’re providing legal advice.”
All of that said, Cohen doesn’t get to simply decide that conversations he had with Trump should be exempt from privilege. Even that discussion of the hush-money payments might not be cleared under crime fraud: Perhaps, Margulies pointed out, Trump could prove that he wasn’t involved in the payments and therefore any conversations weren’t exempted.
Cohen may not even be allowed to answer questions related broadly to his work for Trump. If he were asked how many hush-money agreements existed, that might breach privilege simply because it would reveal information about his conversations with Trump.
If Cohen simply threw caution to the wind and revealed information that is clearly privileged, the ramifications would be limited. Margulies noted that he might be disbarred, but that’s going to happen anyway. Trump could sue, perhaps, but Cohen likely doesn’t have much money to give him. (He might have insurance against such suits, though, Margulies pointed out.)
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https://www.washingtonpost.com/politics/2019/02/26/what-michael-cohen-can-cant-likely-wont-talk-about-while-hes-capitol-hill