WASHINGTON (NewsNation) — Former President Donald Trump returned to Washington to attend a federal appeals court hearing focused on whether he is immune from prosecution on charges that he plotted to overturn the results of the 2020 election.

The outcome of the arguments carries enormous ramifications both for the landmark criminal case against Trump and for the broader, and legally untested, question of whether an ex-president can be prosecuted for acts committed in the White House.

Tuesday’s hearing features a three-judge panel of the U.S. Court of Appeals for the District of Columbia Circuit: Judge Karen Henderson, an appointee of former President George H.W. Bush, and Judge Michelle Childs and Judge Florence Pan, both appointees of President Joe Biden.

Both parties are presenting oral arguments followed by a question-and-answer period with the legal teams.

During lengthy arguments, the judges repeatedly pressed Trump’s lawyer to defend claims that Trump was shielded from criminal charges for acts that he says fell within his official duties as president. That argument was rejected last month by a lower-court judge overseeing the case against Trump, and the appeals judges suggested through their questions that they, too, were dubious that the Founding Fathers envisioned absolute immunity for presidents after they leave office.

“I think it’s paradoxical to say that his constitutional duty to take care that the laws be faithfully executed allows him to violate criminal law,” Henderson said.

Former presidents enjoy broad immunity from lawsuits for actions taken as part of their official White House duties. But because no former president before Trump has ever been indicted, courts have never before addressed whether that protection extends to criminal prosecution.

Trump’s lawyers insist that it does, arguing that courts have no authority to scrutinize a president’s official acts and decisions and that the prosecution of their client represents a dramatic departure from more than two centuries of American history that would open the door to future “politically motivated” cases. They filed a similar motion Monday in another criminal case against Trump in Georgia.

“To authorize the prosecution of a president for his official acts would open a pandora’s box from which the nation may never recover,” said John Sauer, a lawyer for Trump.

He asked: “Could George W. Bush be prosecuted for obstruction of an official proceeding for allegedly giving false information to Congress to induce the nation to go to war in Iraq under false pretenses?”

However, the judges were repeatedly skeptical about those arguments. Pan noted to Sauer that his team concedes that former presidents can be prosecuted for official acts if they are impeached and convicted by the Senate.

She suggested that hurts his absolute immunity claims, telling Sauer that “once you concede that presidents can be prosecuted under some circumstances, your separation of powers argument falls away.”

The judges jumped right into questioning Trump’s lawyer over whether the court has jurisdiction to hear the appeal at this time.

Additionally, Trump’s legal team argues all of the alleged criminal activity happened while Trump was in office, and his decisions to question the 2020 election results was within his duty as president.

Sauer said presidential immunity is a claim that is meant to be reviewed before trial. Special counsel Jack Smith’s team also said that it wants the court to decide the case now.

Despite the attorneys highlighting Trump’s acquittal in impeachment related to the Jan. 6 case, U.S. District Judge Tanya Chutkin, overseeing the trial, rejects this argument. The Special Counsel prosecuting Trump contends that a president can be prosecuted for illegal action to retain power.

“Of course I was entitled, as President of the United States and Commander in Chief, to Immunity. I wasn’t campaigning, the Election was long over. I was looking for voter fraud,” Trump wrote in a Truth Social post, ahead of Tuesday’s hearing.

He also accused President Joe Biden of weaponizing the Department of Justice.

However, during a speech in South Carolina on Monday, Biden took aim at Trump’s actions on Jan. 6.

“For hours the defeated former president sat in a private dining room from the Oval Office and did nothing. Nothing, absolutely nothing. His actions were among the worst dereliction of duty by any president in American history,” Biden said.

A swift ruling is anticipated in Tuesday’s hearing, potentially leading to an appeal to the U.S. Supreme Court from the losing side. Although the federal election interference trial was initially set for early March, it is currently on hold, awaiting the outcome of the appeals process.

The Associated Press contributed to this report.