House Judiciary Chairman Jerry Nadler dropped down the gavel Tuesday morning and held a hearing even though former White House counsel Don McGahn was a no-show.

Trump on Monday instructed Don McGahn to defy a congressional subpoena citing an 8-page legal opinion from the Justice Department arguing he is immune from testifying because he was an advisor to the President.

Nadler accused President Trump of witness intimidation Tuesday over a tweet he posted about McGahn and threatened to take legal action to enforce his subpoena.

“He took to Twitter to call Mr. McGahn a liar. His lawyers went on cable television to do the same,” Nadler said at the committee hearing.

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“In short, the president took it upon himself to intimidate a witness who has a legal obligation to be here today,” Nadler added. “This conduct is not remotely acceptable.”

Nadler continued to threatened McGahn Tuesday morning after sending the counsel a 3-page letter promising “serious consequences” if refuses to testify.

“Our subpoenas are not optional,” Nadler said Tuesday. “Mr. McGahn has a legal obligation to be here for his scheduled appearance. If he does not immediately correct his mistake, this committee will have no choice but to enforce the subpoena against him.”

Doug Collins, the top Republican on the House Judiciary Committee slammed Nadler and said the Democrat is only interested in creating drama.

“Don’t be fooled. The chairman wants the fight and the drama. He does not actually want the information he claims to be seeking,” Collins said. “After the administration made volumes of information available to this committee, the chairman issued overbroad subpoenas and now harangues the administration for being unable to comply with those subpoenas.”

Watch Nadler throw a tantrum: