House Democrats and former deputy national security adviser Charles Kupperman separately asked a federal judge on Monday to block President Trump 's acting chief of staff from intervening in a lawsuit over subpoenas related to the House's impeachment inquiry.

Trump's top aide, Mick Mulvaney , had filed a motion in D.C. District Court on Friday seeking to join Kupperman's lawsuit over a subpoena in order to fight the House Intelligence Committee's efforts to compel his own testimony.

ADVERTISEMENT

But Democrats argued that the original lawsuit is moot since they withdrew the subpoena directing Kupperman to testify.

Kupperman also filed a brief on Monday opposing Mulvaney's motion arguing that he should be directed to file a separate lawsuit.



The Democrats wrote in their filing that even if the case was not moot at this point, Mulvaney and Kupperman are in very different circumstances.

"While Kupperman seeks a declaration from this Court as to whether he should comply with his subpoena or follow the President’s directive, Mulvaney seeks only a declaration that the House Defendants cannot compel him to comply with his subpoena or take any action against him if he does not," they wrote. "Unlike Kupperman, Mulvaney does not state that he would comply with his subpoena if this Court rejects the claimed absolute immunity."