So, Mueller by his own account, conducted a two-year investigation knowing from the beginning that he wouldn’t make the either/or decision that prosecutors exist to make. Attorney General William Barr was right when he told the Senate Judiciary Committee, “At the end of the day, the federal prosecutor must decide yes or no.” Mueller decided neither.

Mueller offered several reasons in his statement for conducting an obstruction investigation anyway. One was to preserve evidence. But for what? The idea that Trump, after losing reelection in 2020, would be prosecuted as a private citizen for firing FBI Director James Comey is manifestly absurd. Another was that a president can be accused of wrongdoing in “a process other than the criminal justice system,” i.e., impeachment by Congress.

Here, Mueller is basically describing Volume 2 as an impeachment referral. But this isn’t a purpose contemplated by the special counsel regulations, which, again, were written to tether special counsels to Justice Department practice.