(Bloomberg) -- President Donald Trump’s acting Chief of Staff Mick Mulvaney asked a judge to determine whether he must comply with a House Intelligence committee subpoena to testify in its impeachment hearings.

Mulvaney is seeking to be added to the lawsuit of Charles Kupperman, the former deputy of National Security Advisor John Bolton, who previously asked the same judge to decide if he must testify even though he was ordered not to by the White House. Bolton is in the same position and has said he would comply with a subpoena if ordered by a judge.

“The House defendants threaten to hold Mr. Mulvaney in contempt or otherwise take adverse action against him for obeying the directive of the head of his branch,” Mulvaney’s lawyer said in a filing late Friday in Washington federal court, referring to the president.

“The question whether the president’s authority must give way in the face of a congressional subpoena -- the determination Mr. Kupperman has asked this court to make -- is central to the question whether the House may take adverse action against Mr. Mulvaney, as threatened,” Mulvaney’s lawyer wrote.

Here’s the Story on Trump, Ukraine and Impeachment: QuickTake

Mulvaney approved a meeting between Ukrainian President Volodymyr Zelenskiy and Trump, if Ukraine agreed to start new investigations into Joe and Hunter Biden, according to a transcript of the testimony of the former top Russia adviser on the National Security Council, Fiona Hill -- which was released Friday.

The demand for the Ukrainian investigation into Trump’s political opponent in the U.S. is at the core of the Congressional impeachment investigation.

Mulvaney was issued a subpoena Thursday and ordered to appear before the Intelligence committee Friday. At the 11th hour, Mulvaney said he was told by White House counsel that due to “constitutional immunity of current and former senior advisers to the president” he must not to appear and testify. Attached was an opinion of the Office of Legal Counsel supporting the order, Mulvaney said.

Mulvaney finds himself “trapped between the commands of two of its co-equal branches -- with one of those branches threatening him with contempt,” his lawyer wrote.

White House Clash

Mulvaney’s request for the court to solve his dilemma comes as he has been clashing with one of the one of the president’s other most senior aides, White House Counsel Pat Cipollone, over who should direct the president’s response to the House impeachment inquiry, according to people familiar with the matter.

Complicating the dispute between the officials, Mulvaney has fallen out of favor with some of Trump’s allies after high-profile stumbles handling the inquiry, and Trump last month privately tested the idea of replacing him. By contrast, Cipollone enjoys the support of Trump and senior adviser Jared Kushner, positioning the lawyer to outlast Mulvaney.

The House had withdrawn Kupperman’s subpoena, saying it would rely on an order in a separate case, involving the demand for testimony from former White House Counsel Don McGahn.

But Kupperman said that order wouldn’t apply to him, and asked the judge to rule on his request. His case is before U.S. District Judge Richard Leon, who was appointed by former President George W. Bush.

The case is Kupperman v. House of Representatives of the U.S.A., 19-cv-03224, U.S. District Court, District of Columbia (Washington).

To contact the reporter on this story: Joe Schneider in Los Angeles at jschneider5@bloomberg.net

To contact the editors responsible for this story: David Glovin at dglovin@bloomberg.net, Joe Schneider, Peter Blumberg

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