WASHINGTON (AP) — With Donald Trump listening intently in the courtroom, federal appeals court judges in Washington expressed deep skepticism Tuesday that the former president was immune from prosecution on charges that he plotted to overturn the results of the 2020 election.

The panel of three judges, two of whom were appointed by President Joe Biden, also questioned whether they had jurisdiction to consider the appeal at this point in the case, raising the prospect that Trump’s appeal could be dispensed with on more procedural grounds.

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 the 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,” said Judge Karen LeCraft Henderson, an appointee of former President George H.W. Bush.

The outcome could carry 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 actions taken in the White House. It will also likely set the stage for further appeals before the U.S. Supreme Court, which last month declined a request to weigh in but could still get involved later.

A swift decision is crucial for special counsel Jack Smith and his team, who are eager to get the case — now paused pending the appeal — to trial before the November election. But Trump’s lawyers, in addition to seeking to get the case dismissed, are hoping to benefit from a protracted appeals process that could delay the trial well past its scheduled March 4 start date, including until potentially after the election.

Underscoring the importance to both sides, Trump, the 2024 Republican presidential primary front-runner, attended Tuesday’s arguments even though the Iowa caucuses are just one week away and despite the fact that there’s no requirement that defendants appear in person for such proceedings. Making his first court appearance in Washington since his arraignment in August, Trump sat at the defense table, watching closely and occasionally taking notes and speaking with his lawyers.

His appearance and his comments afterward underscored his broader effort to portray himself as the victim of a justice system he claims is politicized. Though there’s no evidence Biden has had any influence on the case, Trump’s argument could resonate with Republican voters in Iowa as they prepare to launch the presidential nomination process.

After the hearing, Trump spoke to reporters at The Waldorf-Astoria hotel, which used to be the Trump International Hotel, calling Tuesday “a very momentous day.” He insisted he did nothing wrong and claimed he was being prosecuted for political reasons.

“A president has to have immunity,” he 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 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.

“To authorize the prosecution of a president for official acts would open a Pandora’s box from which this nation may never recover,” said D. John Sauer, a lawyer for Trump, asserting that, under the government’s theory, presidents could be prosecuted for giving Congress “false information” to enter war or for authorizing drone strikes targeting U.S. citizens abroad.

He later added, “If a president has to look over his shoulder or her shoulder every time he or she has to make a controversial decision and wonder if ‘after I leave office, am I going to jail for this when my political opponents take power?’ that inevitably dampens the ability of the president.”

But the judges were skeptical about those arguments. Judges Henderson and Florence Pan noted the lawyer who represented Trump during his 2021 impeachment trial suggested that he could later face criminal prosecution, telling senators at the time: “We have a judicial process in this country. We have an investigative process in this country to which no former office holder is immune.”

“It seems that many senators relied on that in voting to acquit” Trump, Pan told Sauer.

Judge J. Michelle Childs also questioned why former President Richard Nixon would need to be granted a pardon in 1974 after the Watergate scandal if former presidents enjoy immunity from prosecution. Sauer replied that in Nixon’s case, the conduct did not involve the same kind of “official acts” Trump’s lawyers argue form the basis of his indictment.

Aside from the merits of the immunity claim, the judges jumped right into questioning Trump’s lawyer over whether the court has jurisdiction to hear the appeal at this time. Sauer said presidential immunity is clearly a claim that is meant to be reviewed before trial. Smith’s team also said that it wants the court to decide the appeal now.

Smith’s team maintains that presidents are not entitled to absolute immunity and that, in any event, the acts Trump is alleged in the indictment to have taken — including scheming to enlist fake electors in battleground states won by Biden and pressing his vice president, Mike Pence, to reject the counting of electoral votes on Jan. 6, 2021 — fall outside a president’s official job duties.

“The president has a unique constitutional role but he is not above the law. Separation of powers principles, constitutional text, history, precedent and immunity doctrines all point to the conclusion that a former president enjoys no immunity from prosecution,” prosecutor James Pearce said, adding that a case in which a former president is alleged to have sought to overturn an election “is not the place to recognize some novel form of immunity.”

When Judge Henderson asked how the court could write its opinion in a way that wouldn’t open the “floodgates” of investigations against ex-presidents, Pearce said he did not anticipate “a sea change of vindictive tit-for-tat prosecutions in the future.” He called the allegations against Trump fundamentally unprecedented.

“Never before has there been allegations that a sitting president has, with private individuals and using the levers of power, sought to fundamentally subvert the democratic republic and the electoral system,” he said. “And frankly, if that kind of fact pattern arises again, I think it would be awfully scary if there weren’t some sort of mechanism by which to reach that criminally.”

It’s not clear how quickly the panel from the U.S. Circuit Court of Appeals from the D.C. Circuit will rule, though it has signaled that it intends to work quickly.

U.S. District Judge Tanya Chutkan rejected the immunity arguments, ruling last month that the office of the presidency does not confer a “‘get-out-of-jail-free’” pass. Trump’s lawyers appealed that decision, but Smith’s team, determined to keep the case on schedule, sought to leapfrog the appeals court by asking the Supreme Court to fast-track the immunity question. The justices declined to get involved.

The appeal is vital to a Trump strategy of trying to postpone the case until after the November election, when a victory could empower him to order the Justice Department to abandon the prosecution or even to seek a pardon for himself. He faces three other criminal cases, in state and federal court, though the Washington case is scheduled for trial first.

Richer reported from Boston. Associated Press Ashraf Khalil in Washington contributed to this report.