U.S. District Judge Ketanji Brown Jackson in D.C. Credit: Diego M. Radzinschi/ NLJ

A federal judge has ruled that former White House counsel Donald McGahn can be compelled to testify as part of the House's impeachment inquiry.

U.S. District Judge Ketanji Brown Jackson of the District of Columbia, in a 120-page opinion, wrote that "compulsory appearance by dint of a subpoena is a legal construct, not a political one, and per the Constitution, no one is above the law."

And she sharply criticized the Department of Justice for arguing that the case could not be resolved in court, writing those claims "distort established separation-of-powers principles beyond all recognition."

"Thus, ultimately, the arguments that DOJ advances to support its claim of absolute testimonial immunity for senior-level presidential aides transgress core constitutional truths," Jackson wrote.

Department of Justice spokeswoman Kerri Kupec said the department will appeal and request a stay of Jackson's ruling.

The judge repeatedly pointed to a previous district court decision that found former White House counsel Harriet Miers, under then-President George W. Bush, also had to comply with a congressional subpoena.

"Accordingly, if a duly authorized committee of Congress issues a valid legislative subpoena to a current or former senior-level presidential aide, the law requires the aide to appear as directed, and assert executive privilege as appropriate," Jackson wrote.

She further characterized having members of the president's staff testify before Congress as "critical" to lawmakers' oversight functions, rather than "needlessly intrusive and unwarranted." She also rejected the Justice Department's claim that the "threat" of being forced to testify would prevent staff from being able to adequately serve the president.

And she took direct aim at the Justice Department's assertion that McGahn and other similarly situated current and former White House officials are "immune" from testifying, calling that argument "baseless."

"In short, DOJ's implicit suggestion that compelled congressional process is a 'zero-sum' game in which the President's interest in confidentiality invariably outweighs the Legislature's interest in gathering truthful information, such that current and former senior-level presidential aides should be always and forever immune from answering probing questions, is manifestly inconsistent with a governmental scheme that can only function properly if its institutions work together," the opinion reads.

The House Judiciary Committee filed the lawsuit earlier this year, seeking McGahn's testimony as he was witness to several potential acts of obstruction of justice as described in special counsel Robert Mueller's report. The committee subpoenaed McGahn, but he defied the request at the direction of the White House.

McGahn rejoined Jones Day in March after leaving his post at the White House.

The House's current impeachment inquiry has focused on allegations of wrongdoing in relation to withholding military aid from Ukraine in exchange for investigations into President Donald Trump's political rival: former Vice President Joe Biden and his son Hunter.

But House general counsel Douglas Letter has maintained that other allegations of misconduct by the president, including the potentially obstructive acts witnessed by McGahn, remain part of the impeachment inquiry. And he said McGahn's testimony is needed to make sure that no information is left out of the impeachment probe.

The House, less than three weeks after Jackson heard arguments, urged her to issue an "expedited ruling" in the case. "Given that the House's impeachment inquiry is proceeding rapidly, the committee has a finite window of time to effectively obtain and consider McGahn's testimony," the attorneys wrote.

Jackson was seemingly frustrated by DOJ attorney James Burnham's arguments in October that the House can't go to court to enforce the subpoena for McGahn's testimony, and that both current and former White House officials are subject to "absolute immunity" and can't be made to testify.

But Jackson questioned how the House would be able to conduct oversight if it wasn't allowed to call in those kinds of witnesses. And she noted that former administration officials frequently discuss their past experiences, whether as cable new pundits or in books.

"So what does checks and balances mean?" Jackson asked. "How can the legislative actually exercise oversight with respect to the executive, unless it has some ability to enforce its inquiries" on information?

Jackson addressed that same issue in her ruling Monday, writing that "if the purpose of providing certain senior-level presidential aides with absolute testimonial immunity is that the practicalities of their special roles demand it, then what justifies allowing that entitlement to follow them when they return to private life?"

"As a matter of pure logic, it would seem that if one's access to the Oval Office is the reason that a categorical exemption from compelled congressional process is warranted, then that trump card should, at most, be a raincheck, and not the lifetime pass that DOJ proposes," she continued.

The ruling is another victory for the House in court, just weeks after U.S. District Chief Judge Beryl Howell also ruled that lawmakers could access grand jury materials redacted from Mueller's report as part of the impeachment inquiry.

The U.S. Court of Appeals for the D.C. Circuit has granted an administrative stay temporarily stalling Howell's order. It heard arguments Monday in the Justice Department's bid for an emergency stay on handing over the grand jury information, as its appeal plays out in the circuit court.

The three-judge panel weighing the case has scheduled oral arguments on the appeal for Jan. 3.

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