When asked by NBC’s Chuck Todd whether he was asserting that the President has the power to end “any federal investigation,” Giuliani replied “Yeah, that is pretty clear.” Giuliani based that claim on his reading of the Constitution, and the fact that the Attorney General is appointed by the President (though AG Jeff Sessions has recused himself from the investigation).

“The Department of Justice is a creature of the president,” Giuliani said. He acknowledged that this legal reading clashes with long-accepted norms about separation of powers within the executive branch. The “Justice Department is given a tremendous amount of independence. I am tremendously in favor of that. But that is all the president’s decision.”

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That stance mirrors a memo sent to Mueller in January, and reported Friday by the New York Times. The memo argued that the Constitution gives Trump the power to “terminate [Mueller’s] inquiry.” More radically, according to the Times, the memo argues that because he has the power to stop the investigation, President Trump cannot be accused of obstructing the investigation through his actions while it is ongoing. The memo also hinted that the president could have the power to pardon himself if convicted of wrongdoing.

But Giuliani said the president and his legal team would not take those extreme steps – specifically, that Trump would not pardon himself – because “we can win it on the facts.” Giuliani further acknowledged that halting Mueller’s investigation would have huge political consequences, and “could lead to impeachment,” because it would leave Congress and the courts the only formal check on presidential power.

“The whole switch in public opinion that has been on the President’s side,” Giuliani said, “would probably shift back.” That shift, many analysts agree, has come in part because of successful White House efforts to undermine the legitimacy of the Mueller investigation, and of the FBI more broadly.