The state of Maryland is reportedly set to ask a federal judge for an injunction declaring the appointment of acting Attorney General Matthew Whitaker illegal, and Judge Andrew Napolitano agrees that Whitaker is not "legally qualified" for the role.

Maryland is likely to make the unprecedented move on Tuesday in a bid to block Whitaker from exercising the duties in the position, arguing that his appointment is not legitimate. The state will reportedly claim that deputy attorney general Rod Rosenstein is the rightful acting attorney general.

Whitaker’s appointment has been under fire ever since it was announced last week, coinciding with the resignation of then-Attorney General Jeff Sessions, with Democrats questioning his qualifications and views on Special Counsel Robert Mueller’s investigation.

On "Fox & Friends" Tuesday, Napolitano, Fox News' senior judicial analyst, explained why he agrees with the state of Maryland that it was an "unlawful appointment."

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He said there are two statutes that govern who can become acting attorney general and they share two requirements: the candidate must be at the Justice Department in a role that was a.) appointed by the president and b.) approved by the Senate.

Napolitano said Congress was very specific when it set those requirements because it didn't want someone managing thousands of DOJ employees and running thousands of investigations who had not been vetted by the Senate.

"Mr. Whitaker ... was not in a position in the DOJ where he was appointed by the president or approved by the Senate. He was just hired by Jeff Sessions to be his chief of staff," Napolitano explained.

"I believe that the Maryland argument is the correct one," he added. "This person is not legally qualified to be attorney general under the statutes the Congress has written." 

He acknowledged that Sessions' firing was destabilizing to the DOJ, and getting rid of his successor would be even more destabilizing.

"We're almost at the point of the Saturday Night Massacre in the Nixon administration when you didn't even know who was running the DOJ or the FBI," Napolitano said. "You can't have musical chairs, but you have to have a lawfully appointed person in there, because he's sixth in line to the presidency. The power that he has with respect to criminal prosecutions is awesome, and he must have undergone Senate vetting before he can have it."

Watch more from the judge above.

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