Former Obama administration acting Solicitor General Neal Katyal co-wrote a scathing op-ed piece in The New York Times on Thursday, claiming that President Donald Trump violated the Constitution with his appointment of Matthew Whitaker as acting Attorney General. Then he went on MSNBC’s “All In with Chris Hayes” to elaborate on his position and discuss the possible legal ramifications of Trump’s selection.

“The Constitution flatly prohibits Mr. Whitaker from being the acting Attorney General,” Katyal said. The gist of his argument is that the Appointments Clause of the Constitution requires that “principal officers” and department heads have to be confirmed by the Senate, and the U.S. Attorney General is a prime example of such a position.

Katyal called Whitaker “essentially a constitutional nobody” for not having been confirmed by the Senate. Whitaker served as U.S. Attorney for the Southern District of Iowa from 2004-2009 and was confirmed by the Senate for that position, but before taking over as acting AG he had been Jeff Sessions‘ chief of staff, a position for which there was no Senate confirmation.

Katyal admitted that “it’s one thing if it’s an emergency or something like that,” but claimed “this is the opposite of that,” because Trump could have named people like Deputy Attorney General Rod Rosenstein or Solicitor General Noel Francisco, who have both been confirmed by the Senate for their current positions.

“The Attorney General has awesome power,” Katyal said. “The powers literally to put someone to death, or to supervise the Solicitor General or the 94 U.S. Attorney prosecutors.”

In light of that responsibility, he explained how easy it would be for a lawsuit to arise over Whitaker’s appointment.

“Every litigant in this country who’s facing the Justice Department can make these arguments and say, ‘Hey you’re trying to put me in jail, Justice Department? You don’t have the authority, you have a fake Attorney General.'”

He also said Senators would have standing to sue, because they have Constitutional control over Attorney General confirmations, and they were not given the opportunity to confirm Whitaker for the job.

“The list of people who can sue is, frankly, endless,” Katyal said.

[Image via MSNBC screengrab]

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