Chairman Elijah Cummings hinted Monday that his House Committee on Oversight and Reform is preparing to unleash a series of subpoenas starting this week for their investigation into the White House’s security clearance policy.

Cummings plans to authorize a subpoena on Tuesday for former White House personnel security director Carl Kline, who now works at the Department of Defense. Kline, who served in the White House for the first two years of Trump’s administration, did not respond to letters from the Oversight Committee in February and March asking him to come in for a voluntary interview.

Cummings indicated in a letter to the White House on Monday that the subpoena for Kline is the first of many the committee has in its back pocket to compel witnesses to come forward for information about potential abuses of the White House’s security clearance policy.

The committee wants to interview, among others, former Chief Security Officer Cory Louie, Chief Operating Officer Samuel Price, former Deputy Chief of Staff Joseph Hagin and Deputy Director of Administration William Hughes.

The White House has actively resisted Cummings’ probe into the security clearance issue after multiple media outlets reported last year that President Donald Trump personally overrode the decisions of career security officials not to give clearances to senior advisers Ivanka Trump and Jared Kushner, the president’s daughter and son-in-law, in addition to others.

The committee has tried to schedule interviews with potential witnesses, but the White House has “sought to block these witnesses from cooperating” with the probe, Cummings wrote in a memo to other committee members Monday.

“The Committee now plans to proceed with compulsory process and begin authorizing subpoenas, starting at tomorrow’s business meeting,” Cummings wrote in a letter to the White House Monday, citing “grave reports” from a whistleblower who met with the committee over the weekend.

That whistleblower, Tricia Newbold, an 18-year employee for the Executive Office of the President who manages security clearance adjudications, told the committee on Saturday that clearance decisions “were not always adjudicated in the best interest of national security” and that the administration overturned more than two dozen adjudications, according to Cummings letter.

Rep. Jim Jordan, the top Republican on the Oversight Committee, accused Cummings on Monday of using Newbold’s testimony as a “pretense for a partisan attack on the White House.”

Jordan lambasted Cummings for not informing committee members of Newbold’s interview — which was on Saturday at 8:30 a.m. — until 3:30 p.m. the day before, preventing Republicans from adequately preparing their questions. Cummings has indicated that he kept the date and time of the interview with Newbold under wraps to protect her from criticism before her interview.

“Chairman Cummings’ investigation is not about restoring integrity to the security clearance process, it is an excuse to go fishing through the personal files of dedicated public servants,” Jordan said in a statement Monday.

Cummings has accused Trump of engaging in “an unprecedented level of stonewalling, delay and obstruction” after the president and his administration have failed to provide “a single piece of paper” for any of the Oversight Committee’s roughly half-dozen investigations.

The Oversight Committee has requested a trove of documents about the Trump administration and transition team’s security clearance process and has identified at least nine people — including former national security adviser Michael Flynn, cable news pundit and former Trump administration official Sebastian Gorka, and Kushner and Ivanka Trump — whose security clearances Democrats believe deserve more scrutiny.

Former White House chief of staff John Kelly and former White House counsel Don McGahn both wrote internal memos over their concerns about Kushner receiving a clearance, according to a New York Times report.

The Times also reported that Trump had lied to the paper when he told reporters in a January interview about his involvement in granting a security clearance to Kushner.

Trump ordered Kelly to grant Kushner a security clearance despite concerns flagged by intelligence officials and McGahn, the Times reported.

In her interview before the Oversight Committee on Saturday, Newbold suggested that she feared retaliation from the administration for her role as a whistleblower.

But she went through with the interview anyway, she said, because she wanted to restore “integrity” to the security clearance process.

“I would not be doing a service to myself, my country, or my children if I sat back knowing that the issues that we have could impact national security,” Newbold said.

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