Neither Mr. Mulvaney nor his lawyers asked Mr. Kupperman, Mr. Bolton or their lawyer to join the suit, nor did they give them advance notice. Mr. Bolton and Mr. Kupperman now have to decide whether to support or oppose including Mr. Mulvaney in their action.
“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,” the lawyers, William Pittard and Christopher C. Muha, wrote in their motion. “For that reason, Mr. Mulvaney seeks to intervene here.”
The lawyers noted that Mr. Mulvaney “finds himself caught in that division, trapped between the commands of two of its coequal branches — with one of those branches threatening him with contempt.” But his situation is even more acute than Mr. Kupperman’s, the lawyers, added, and not just because he still works in the White House.
“Mr. Mulvaney is both a closer and a more senior adviser to the president than was Mr. Kupperman,” they wrote, noting that he has a cabinet-level position. “And, as the acting White House chief of staff, Mr. Mulvaney is among the most regular advisors of the president.”
Mr. Mulvaney’s decision to try to join the lawsuit was also puzzling because House Democrats have withdrawn their subpoena for Mr. Kupperman and made clear they do not want to fight a court battle to obtain his testimony or Mr. Bolton’s.
Mr. Cooper, representing Mr. Bolton, wrote to the House on Friday that his client possessed evidence important to the investigation but would not testify without a clarifying court ruling. Mr. Bolton, Mr. Cooper wrote, “was personally involved in many of the events, meetings, and conversations about which you have already received testimony, as well as many relevant meetings and conversations that have not yet been discussed in the testimonies thus far.”
Peter Baker reported from Tuscaloosa, and Maggie Haberman from New York.