Constitutional expert and "Life, Liberty & Levin" host Mark Levin said on "Hannity" that new revelations about Robert Mueller's investigation into President Donald Trump and alleged Russian collusion appear to render the probe unconstitutional.

Levin said a new "special status" given to several of Mueller's prosecutors in the arm of the probe involving former Trump campaign chief Paul Manafort may be key to invalidating the entire investigation.

Levin said the attorneys in the case before an Alexandria, Va. federal judge are simultaneously considered "Special Assistant U.S. Attorneys."

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He said that therefore, their direct supervisor -- Mueller -- should be lawfully considered a "roving" U.S. Attorney.

He said the Constitution designates the president as the person who must nominate all "principal officers" -- including U.S. attorneys and cabinet members.

But, Mueller was appointed by Deputy Attorney General Rod Rosenstein and was not confirmed by the Senate, as anyone working as a U.S. attorney should be by law, according to Levin.

Levin said that the scenario therefore "violates the Constitution [via] the Appointments Clause" in Article II.

"Rosenstein usurped the authority of the president of the United States to nominate whoever he wants as a prosecutor," Levin said.

"Mr. Mueller is serving unconstitutionally in violation of the Appointments Clause of the U.S. Constitution because of the way Rod Rosenstein appointed him."

Levin called on every defendant in the Mueller probe and all attorneys for those subpoenaed or affected to raise the issue of the Appointments Clause in court.

"The breadth of his investigation is so massive, so broad [that] four of his own people get dual appointments [as assistant U.S. attorneys]," he added.

Watch more above.

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