Trump probably thought if he had an attorney do his dirty work, he could hide it all

behind the shield of attorney-client privilege.

This theory was proven wrong long ago.

Guess who proved it wrong? John Gotti, former head of the Gambino crime family, whose attorney wasn't allowed to represent him because he was a participant in criminal conversations captured on audiotape.

John Gotti had been called the "teflon Don" because it took three trials before a prosecutor could get a conviction. Guess who finally put him away?

Robert Mueller.

https://lawfareblog.com/michael-cohen-attorney-client-privilege-and-crime-fraud-exception

First, for the attorney-client privilege to exist, there must actually be an attorney-client relationship regarding a specific matter. I, for instance, have to hire you to help me resolve a tax dispute with the IRS. The representation is limited to that matter and so is the privilege. Other things I may have told you in passing (for example, about the fight I am having with my wife and how I beat her—this is a hypothetical!) are outside the scope of the representation and are not privileged. The law is clear that as a general matter a person cannot claim to have an attorney for “all matters” that might arise. (As an aside, one reason for this rule is that it would frustrate legitimate investigation—as was the case when John Gotti, the famous Mafia don, suggested that his attorney, Bruce Cutler, represented him in everything—thereby attempting to make it unlawful for the government to wiretap or use an undercover agent to speak to him about new matters.) Indeed, the cases are legion for the proposition that representation of a defendant in connection with one criminal matter does not encompass representation in connection with a separate (and even arguably related) criminal matter. (For one example, see Illinois v. Perkins, 496 U.S. 292, 299 (1990), which says a defendant charged with aggravated battery may be contacted undercover in a murder investigation.)

Why is this relevant? Because President Trump has said quite publicly that he did not know what Cohen was doing with respect to the alleged payments to the actress known as Stormy Daniels—payments that appear to be at the core of the Southern District of New York's investigation. He has said that he was unaware of the payments and did not know why they were made (and suggested that the press had to “ask Michael” about them). If this is true, then it seems that Trump could not have had an attorney-client relationship with Cohen regarding the Daniels payment in the first instance—one hallmark of an attorney-client relationship is agreement as to its scope and the attorney’s obligation to keep the client advised as to all significant material matters (of which settlement would surely be one). By his own testimony, it seems that the Daniels matter is outside the scope of matters in which Cohen has represented Trump—and thus there is no attorney-client privilege in the first instance.

But let’s assume the contrary. Let's assume that Trump and Cohen did have an agreement (and that Trump is not being candid about what he knew—which is another kettle of fish altogether). If that is the case then clearly the discussions between Trump and Cohen would fall within the attorney-client privilege. Trump might have told Cohen about his version of what really happened; might have asked Cohen to make sure his wife did not find out; and might have promised to pay Cohen back for the settlement funds. All of these hypotheticals (again, we don’t really know) are the sorts of confidential communications that are presumptively protected by the privilege. And the privilege applies whether these communications happened orally or in writing.

What then could be the basis for the Southern District of New York search and review of these materials? Materials that, at least facially, would be protected.

That question brings us to something known as the crime-fraud exception to the attorney-client privilege.

SNIP