President Trump is pulling out all the stops to prevent Special Counsel Robert Mueller from testifying before Congress, and as long as Mueller works at the Justice Department, he needs sign-off from Attorney General William Barr to testify. Barr has said publicly that he has "no objection to Bob Mueller personally testifying," he reportedly hasn't changed that position, and he told the Senate last week that the White House isn't exerting influence on whether Mueller should be allowed to testify.

House Democrats have tentatively scheduled Mueller to testify on May 15. Once Mueller leaves the Justice Department, Trump will have even less control over whether he testifies, and Peter Carr, a spokesman for the special counsel's office, told The Hill on Monday that Mueller "will be concluding his service within the coming days." He did not elaborate. "Coming days" is pretty vague, and Carr, it should be noted, used the same phrase a month ago; on April 5, he told Quartz that Mueller "will be concluding his service within the coming days."

Mueller, who is reportedly open to testifying before Congress, has agency in this, too. "They could instruct him not to appear voluntarily, but then Congress would just subpoena him, and I don't think there is any basis for fighting the subpoena," Randall Eliason, a George Washington University law professor, tells The Hill. "If they tell him not to go and he wants to go, he can quit and then go." Peter Weber