The House's top lawyer Monday urged a three-judge panel at the U.S. Court of Appeals for the D.C. Circuit to quickly issue a ruling on whether they'll allow certain lawmakers to obtain grand jury materials redacted from the Mueller report, saying that information could show whether President Donald Trump was "untruthful" in his answers to then-special counsel Robert Mueller.

House general counsel Douglas Letter, arguing before Judges Neomi Rao, Thomas Griffith and Judith Rogers, said the grand jury information redacted from the Mueller report remains key to the House's ongoing impeachment inquiry, as lawmakers hold hearings on allegations of improper withholding of military aid from Ukraine.

"We have at least two people that have already been convicted of lying to Congress," Letter said. "And what are they lying about? They're lying about things that go directly to the Mueller report."

Letter, echoing previous court filings, said the grand jury information could be used to determine whether the president was truthful in his written responses in the Mueller investigation.

The significance of Trump's accuracy in those written responses was heightened by a tweet from the president Monday morning, in which Trump said he would "strongly consider" giving written testimony as part of the House's impeachment inquiry.

The arguments were made on a motion by the Justice Department for a stay pending their appeal of U.S. District Chief Judge Beryl Howell's order requiring the information be handed over to the House by Oct. 30. The circuit court had already granted an administrative stay on that order, as they considered the motion for a stay.

Letter on Monday argued the court could skip ahead to a ruling on the merits of the appeal. That push for expediency is in line with the speed of the House's impeachment inquiry, which is expected to be completed by the end of the calendar year.

Department of Justice lawyer Mark Freeman said he recognized the judges' authority to quickly rule on the merits, but that he did not think they should do so in this case. Rather, he said the court should simply issue a stay on the district court's order to turn over the grand jury materials and let the appeal be fully briefed.

Rao, a Trump-appointed judge who has authored dissenting opinions against the disclosure of Trump's financial records to the House, pressed Letter on why the Justice Department had not met the qualifications for a stay in the appealed.

She noted the DOJ's argument that it would suffer "irreparable harm" if the information were to be given to Congress.

Letter said there are safeguards to keep the grand jury material protected, but acknowledged the House Intelligence and Judiciary Committees could vote to release the materials if they felt it important enough to be made public. He also noted that prior grand jury materials given to Congress during Watergate were never released.

"Recent history suggests that some norms aren't in place" that were at the time of Watergate, Griffith replied.

Freeman, the Justice Department attorney, argued to the panel that an impeachment proceeding is not a judicial proceeding, in the context of the statute that lays out when grand jury materials can be released.

But the judges noted prior rulings from the circuit court that found that impeachment is a judicial proceeding, raising questions about how they could rule otherwise in this case.

And they pressed Freeman over the DOJ's current opposition to the release of grand jury materials, as the department hadn't opposed it during past impeachment proceedings, most notably Watergate.

Freeman said the department had worked on an "erroneous assumption" in the past about how to interpret the grand jury secrecy statute, and was now correcting that stance.

However, Rogers questioned how the House would be able to obtain the grand jury materials otherwise, without getting those who testified before Mueller's grand jury to agree to be witnesses in the impeachment inquiry.

Freeman replied that was the department's stance—that Mueller witnesses would have to testify again. And he said that if Congress valued the grand jury materials, it should amend the secrecy law to explicitly allow lawmakers to gain access to them.

Letter said he didn't believe the House had to amend the rule, and noted it's included among the federal rules of criminal procedure, meaning the U.S. Supreme Court could also change the statute if it wished.

The House lawyer also took issue with Freeman's claim that impeachment raises a "political question," meaning that it cannot be resolved by a court.

"It cannot possibly be that it was a political question," Letter said, pointing to the court rulings in Watergate.

And he said it would create an "absurd situation" where civil litigants or the media could get the grand jury materials, but that Congress could not.

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