Last week, the FBI executed a search warrant at the office of Michael Cohen, a lawyer who has worked for President Trump. The Washington Post reports that Cohen is being “investigated for possible bank and wire fraud,” perhaps in connection with “buy[ing] the silence of people who . . . could have damaged Trump’s candidacy in 2016.” The New York Times story on the matter is here. President Trump and others have suggested that the execution of the warrant was inappropriate because it infringes on the attorney-client privilege. Without getting into the politics, what do we know about the law?