Fox News senior judicial analyst Judge Andrew Napolitano appeared on "Fox & Friends" Thursday to explain why President Trump's pick for acting attorney general after Jeff Sessions' resignation is professionally but not legally qualified for the role.

Following Sessions' abrupt resignation on Wednesday, President Trump tweeted that Matthew Whitaker, chief of staff to Sessions, will become the acting attorney general.

Whitaker, according to sources, is now overseeing everything at the Justice Department, including the Russia investigation -- despite calls from Democrats to recuse himself. Trump said a permanent replacement will be nominated at a later date.

Napolitano said Whitaker, however, is not legally qualified for the role of acting attorney general because of "very precise laws" written by Congress in the wake of the Watergate scandal.

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He said there are only three ways someone can become acting attorney general: if they are the deputy attorney general and the president signs an executive order to make them acting attorney general, if they are already at the Justice Department in a job that both required and received Senate confirmation or if the Senate in in recess, they can be a recess appointment.

He said none of those apply in this case, as Whitaker is not deputy attorney general, he did not receive Senate confirmation for his current role at the DOJ and the Senate is not in recess.

"So with deference and respect to what the president's trying to do -- he has every right to want whoever he wants to run the Justice Department -- he has chosen someone who does not qualify under the law to be the acting attorney general of the United States," Napolitano said.

Get more insight from Napolitano above.

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