The House Judiciary Committee told a federal appeals court on Monday that it is still seeking testimony from former White House counsel Don McGahn because he could provide information that would help the panel decide whether to recommend additional articles of impeachment against President Trump Donald John TrumpBiden says voters should choose who nominates Supreme Court justice Trump, Biden will not shake hands at first debate due to COVID-19 Pelosi: Trump Supreme Court pick 'threatens' Affordable Care Act MORE.

The committee submitted a brief to the D.C. Circuit Court of Appeals arguing that its subpoena of McGahn is not moot following the House's vote to approve two articles of impeachment.

"If McGahn’s testimony produces new evidence supporting the conclusion that President Trump committed impeachable offenses that are not covered by the Articles approved by the House, the Committee will proceed accordingly — including, if necessary, by considering whether to recommend new articles of impeachment," the panel wrote in its filing.

ADVERTISEMENT

The committee also said that McGahn's testimony would be crucial for helping the House present its case against Trump in an upcoming Senate trial over the approved impeachment articles.

The panel subpoenaed McGahn in March as part of an investigation into potential obstruction by the Trump White House. That investigation culminated earlier this month when the House approved an article of impeachment for obstruction of Congress.

Trump ordered McGahn, who left the White House in 2018, not to comply with the subpoena and the Department of Justice (DOJ) asserted in court that the president and his close advisers have absolute immunity from congressional subpoenas.

The department appealed to the D.C. Circuit after a federal judge rejected its argument and ordered McGahn to comply with the subpoena. The subpoena has been stayed while the court fight plays out.

After the House voted to impeach Trump last week, a three-judge panel on the D.C. Circuit asked both sides in the case to brief the court on whether the fight over the subpoena was moot.

The Judiciary Committee on Monday also argued that it's important for it to pursue the case to help settle long unanswered questions about executive power.

ADVERTISEMENT

"When the Committee subpoenas another Presidential aide — whether as part of its ongoing investigations or in future investigations — it is likely again to confront DOJ’s theory that Presidential advisors are absolutely immune from compelled Congressional testimony," the Judiciary filing reads. "The Court should address and reject that theory now."

Both sides will offer oral arguments before the D.C. Circuit on Jan. 3.

Updated at 2:22 p.m.