Fox News Senior Judicial Analyst Judge Andrew Napolitano said Wednesday it was incredible that the Justice Department reached back to a short-term Reconstruction-era presidential appointment to legitimize President Trump's decision to make former Iowa federal prosecutor Matt Whitaker the acting U.S. attorney general.

"I'm very disappointed to see lawyers who work for Matthew Whitaker go back to 1866 and look for a precedent [to keep him in his job]."

"I don't care what happened in 1866," Napolitano said. "Congress changed the law in the 1960s."

Napolitano said the Justice Department pointed all the way back to an appointment by President Andrew Johnson of an attorney general who served for six days and was never confirmed by the Senate.

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Napolitano said the statutes governing the appointments of deputy attorneys general were changed in the 1960s because their roles evolved to the point where "we put too much power in their hands."

He said that the power of the Justice Department cannot "go to a political hack," adding that the way to absolve a political appointment of the suspicion of being a "hack" nomination is to have their candidacy confirmed by the U.S. Senate.

Napolitano added that if Whitaker's appointment is found to be illicit, it would likely make his decisions "null and void" -- which would be problematic if they greatly affect the nation, like a potential constraint of Special Counsel Bob Mueller.

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