A three-judge panel of the federal appeals court in Washington heard arguments on Tuesday in a momentous case over former President Donald J. Trump’s claim that he is immune from criminal charges for the efforts he took to overturn the 2020 election.A ruling by the court — and when it issues that decision — could be a major factor in determining when, or even whether, Mr. Trump will go to trial in the federal election case.Here are some takeaways:All three judges signaled skepticism with Trump’s position.The judges on the Court of Appeals for the District of Columbia Circuit appeared unlikely to dismiss the charges against Mr. Trump on grounds of presidential immunity, as he has asked them to do. The two Democratic appointees on the court, Judge J. Michelle Childs and Judge Florence Y. Pan, peppered John Sauer, a lawyer for Mr. Trump, with difficult questions.Judge Karen L. Henderson, the panel’s sole Republican appointee, seemed to reject a central part of Mr. Trump’s argument: that his efforts to overturn his loss to President Biden cannot be subject to prosecution because presidents have a constitutional duty to ensure that election laws are upheld.“I think it’s paradoxical to say that his constitutional duty to take care that the laws be faithfully executed allows him to violate the criminal law,” Judge Henderson said.U.S. District Court via Associated PressStill, Judge Henderson also expressed worry that allowing the case to proceed could “open the floodgates” of prosecutions of former presidents. She raised the possibility of sending the case back to the Federal District Court judge overseeing pretrial proceedings, Tanya S. Chutkan, for greater scrutiny of how to consider Mr. Trump’s actions.A lawyer for Trump took a sweeping position on a hypothetical assassination.Judge Pan asked Mr. Sauer to address a series of hypotheticals intended to test the limits of his position that presidents are absolutely immune from criminal prosecution over their official acts, unless they have first been impeached and convicted by the Senate over the same matter.Among them, she asked, what if a president ordered SEAL Team 6, the Navy commando unit, to assassinate a president’s political rival? Mr. Sauer said such a president would surely be impeached and convicted, but he insisted that courts would not have jurisdiction to oversee a murder trial unless that first happened.To rule otherwise, Mr. Sauer said, would open the door to the routine prosecutions of former presidents whenever the White House changes partisan hands.U.S. District Court via Associated PressA prosecutor argued that absolute immunity would be ‘frightening.’Picking up on the hypothetical of a president who uses SEAL Team 6 to kill a rival and then escapes criminal liability by simply resigning before he could be impeached or by avoiding a conviction in the Senate, James I. Pearce, a lawyer for the special counsel Jack Smith, denounced Mr. Sauer’s argument. Such a rationale, he added, put forth an understanding of presidential immunity that was not just wrong but also a vision for “an extraordinarily frightening future.”He also rejected the idea that allowing the case to go forward would be a “sea change” that opened the door to “vindictive tit-for-tat prosecutions in the future.” Instead, he said, the fact that Mr. Trump is the first former president ever to be charged with crimes underlined the “fundamentally unprecedented nature” of the criminal charges. He continued: “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.”Mr. Pearce added, “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.”U.S. District Court via Associated PressTrump tried to engage in political theater.In an unusual move, Mr. Trump showed up in person at the appeals court hearing, even though he was not obliged to be there. But if he was hoping to turn the appearance to his political advantage, the effort fell a little flat.He was ushered into the federal courthouse through a heavily guarded back entrance and did not address the dozens of reporters covering the proceedings. And during the hearing itself, he was silent, doing little more than exchanging notes with his lawyers and staring at the judges who will decide his fate.Afterward, Mr. Trump was driven a few blocks away to the Waldorf Astoria Hotel, which once operated under his name, and denounced his prosecution on the election interference charges. He also repeated his false claims that there had been widespread fraud in the 2020 election.“We had a very momentous day in terms of what was learned,” he told reporters. “I think it’s very unfair when a political opponent is prosecuted.”What’s next: The judges will rule, but the timing is not clear.It is not clear when the appellate panel will hand down its ruling. Depending on its outcome, either Mr. Trump or prosecutors could appeal it. The case could be appealed to the full court of appeals — all 11 active judges — or directly to the Supreme Court.Either one of those courts could decide whether to take up the matter or decline to get involved and leave the ruling by the panel in place.How quickly all of this plays out could be nearly as important as the ultimate result. After all, the trial judge, Tanya S. Chutkan, has frozen the underlying case until the immunity issue is resolved. For now, the case is set to go in front of a jury in early March, but protracted litigation could push it back — perhaps even beyond the November election.If that were to happen and Mr. Trump were to win the election, he could try to pardon himself or otherwise use his control of the Justice Department to end the case against him.Christina Kelso More