There are more than 750 pages of records that former President Donald Trump wants to keep out of the hands of investigators on the Jan. 6 Committee. On Tuesday, a panel of federal appeals judges will hear oral arguments in that legal fight, potentially setting the stage for a showdown at the Supreme Court.

There are call logs; speech drafts; diaries; emails; calendars and schedules; memos; and other records that the Jan. 6 Committee has sought from Trump for months as a part of its probe into the violent attack on the U.S. Capitol earlier this year. Investigators believe that these records could illuminate exactly how Trump tried to subvert the election and disrupt a peaceful transfer of power.

Trump will ask the court to overturn D.C. District Judge Tanya Chutkan’s ruling that permitted the National Archives and Records Administration to transmit heaps of Trump’s presidential records to the committee after President Joe Biden opted to waive executive privilege over the materials. Biden explained his reasoning last month, saying that Trump’s assertion to privilege was “not in the best interest of the United States.”

Trump’s legal team pushed back by saying the former president could override the incumbent’s wishes, but Chutkan brushed off the argument, saying: “Presidents are not kings and the plaintiff is not president.” In response, Trump’s attorneys agreed but emphasized that Congress, also, fails to have “unchecked” constitutional power over all systems of government.

On Tuesday at the U.S. Court of Appeals for the District of Columbia, Judges Kentanji Brown Jackson, Robert Wilkins, and Patricia Millet will hear the case. Jackson is a Biden appointee and Wilkins and Millet were named to the bench by former President Barack Obama.  

Most of the files at dispute are from key Trump administration figures already under the committee’s scrutiny, including former Chief of Staff Mark Meadows.

Historically, the Supreme Court has found that former presidents have some say in what happens to their records after leaving office. But a ruling over whose executive privilege rules the day—an incumbent or a former—has never been issued, making this protracted fight between Trump and Congress somewhat novel.

Should the appeals court rule in line with Chutkan, it could mean Trump’s records would finally see the light of day. But given his track record, Trump would very likely appeal such a ruling. That appeal could go one of two ways: the case could be heard before the full panel of judges—all 11 of them—on the appeals court, or Trump could appeal to the Supreme Court.

This story is developing.