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On Monday night, White House Deputy Counsel Michael Purpura informed House Oversight Committee Chair Elijah Cummings (D-Md.) that acting Chief of Staff Mick Mulvaney had ordered former White House security clearance chief Carl Kline to defy a subpoena and skip a deposition scheduled for Tuesday. Kline's lawyer said in a separate letter that his client, who now works at the Defense Department, would comply with the White House's order. "With two masters from two equal branches of government, we will follow the instructions of the one that employs him," said the lawyer, Robert Driscoll.

The House Oversight Committee is investigating how President Trump's White House approves security clearances. It subpoenaed Kline in early April after a whistleblower, career White House Personnel Security Office staffer Tricia Newbold, testified that Kline had overruled his staff and approved at least 25 security clearance applications rejected due to serious red flags, then retaliated against her when she spoke out. One of the senior officials whose application Kline approved despite significant concerns was reportedly Jared Kushner, Trump's son-in-law.

Earlier Monday, Cummings had rejected the White House's request that someone from the White House counsel's office attend the deposition with Kline, saying his committee would hold Kline in contempt if he ignored the subpoena.