Federal prosecutors don't typically raid law offices, because communications between an attorney and clients are generally protected and cannot be used as evidence against the client. So Monday's raid on Michael Cohen's law office, as well as his home and hotel room, was bold and unusual, requiring sign-off from the U.S. attorney in Manhattan — a Trump appointee — a magistrate judge, and the criminal division at the Justice Department, as former U.S. Attorney Preet Bharara explained on CNN:
"It's a tactic generally used against organized crime, against very serious, very serious criminals and lawyers who are operating outside of the protections of the law," Alan Dershowitz, who frequently defends President Trump on cable news, told The Daily Beast. The FBI agents likely brought along a "taint team," or a group of government lawyers walled off from the investigation who go through seized documents to determine which ones prosecutors can see.
Trump is Cohen's sole client, and "Cohen is Trump's virtual vault — the keeper of his secrets, from his business deals to his personal affairs," The Washington Post notes. Cohen's lawyer, Steve Ryan, said the search resulted in the "seizure of protected attorney-client communications between a lawyer and his clients," but Trump's communications with Cohen aren't necessarily shielded, The Wall Street Journal explains:
Attorney-client information may not be protected if the communications were in service of an illegal act, under the "crime-fraud exception" to the privilege. If agents were after Mr. Cohen's client files, prosecutors could still use the information if they found an intention of committing or concealing a crime or fraud, a difficult standard to meet. [The Wall Street Journal]
"The only excuse for raiding a lawyer's office is if the lawyer is potentially involved in crime — if there's probable cause to believe that the attorney is either involved in crime or his services are being used for that," white-collar defense attorney Sol Wisenberg tells The Daily Beast. Which isn't great news for either Trump or Cohen.