Lawyers for Donald Trump made a longshot argument Friday that the Justice Department prosecutor who charged the former president with hoarding classified documents at his Florida estate was illegally appointed and that the case should therefore be dismissed.

The challenge to the legality of special counsel Jack Smith's appointment kicked off a three-day hearing that is set to continue next week and bring further delays to a criminal case that had been scheduled for trial last month but has been snarled by a pileup of unresolved legal disputes. The motion questioning Smith's selection by the Justice Department is one of multiple challenges to the indictment the defense has raised, so far unsuccessfully, in the year since the charges were brought.

U.S. District Judge Aileen Cannon heard hours of arguments Friday from lawyers for both sides, with Trump attorney Emil Bove asserting that the Justice Department risked creating a "shadow government" through the appointment of special counsels to prosecute select criminal cases. Prosecutors say there was nothing improper or unusual about Smith's appointment, with James Pearce, a member of Smith's team at one point saying: "We are in compliance. We have complied with all of the department's policies."

Cannon did not immediately rule, but in an apparent sign that she was taking seriously the Trump team motion, grilled Pearce on what oversight role Attorney General Merrick Garland — who appointed Smith — had in seeking the indictment.

Pearce said he was not in a position to answer the question but noted, "I don't want to make it seem like I'm hiding something."

Even as Smith's team looks to press forward on a prosecution seen by many legal experts as the most straightforward and clear-cut of the four prosecutions against Trump, Friday's arguments didn't concern the allegations against the former president. They centered instead on arcane regulations governing the appointment of Justice Department special counsels like Smith, reflecting the judge's continued willingness to entertain defense arguments that prosecutors say are frivolous and meritless, contributing to the indefinite cancelation of a trial date.

Cannon, a Trump appointee, had exasperated prosecutors even before the June 2023 indictment by granting a Trump request to have an independent arbiter review the classified documents taken from Mar-a-Lago — an order that was overturned by a unanimous federal appeals panel.

Since then, she has been intensely scrutinized over her handling of the case, including for taking months to issue rulings and for scheduling hearings on legally specious claims — all of which have combined to make a trial before the November presidential election a virtual impossibility. She was rebuked in March by prosecutors after she asked both sides to formulate jury instructions and to respond to a premise of the case that Smith's team called "fundamentally flawed."

The New York Times, citing two anonymous sources, reported Thursday that two judges — including the chief federal judge in the southern district of Florida — urged Cannon to step aside from the case shortly after she was assigned to it.

The hearing is unfolding just weeks after Trump was convicted in a separate state case in New York of falsifying business records to cover up a hush money payment to a porn actor who has said she had sex with him. Meanwhile, the Supreme Court is poised to issue within days a landmark opinion on whether Trump is immune from prosecution for acts he took in office or whether he can be be prosecuted by Smith's team on charges that he schemed to overturn the results of the 2020 presidential election.

At issue in Friday's hearing is a Trump team claim that Smith was illegally appointed in November 2022 by Garland because he was not first approved by Congress and because the special counsel office that he was assigned to lead was not also created by Congress.

Smith's team has said Garland was fully empowered as the head of the Justice Department to make the appointment and to delegate prosecutorial decisions to him. They note that a similar argument failed in a challenge to the appointment of Robert Mueller, who was tapped as special counsel by the Trump administration Justice Department to investigate potential ties between Russia and Trump's 2016 campaign.

The hearing continues Monday when the two sides again discuss matters related to Smith's appointment, as well as a limited gag order that prosecutors have requested to bar Trump from comments they fear could endanger the safety of FBI agents and other law enforcement officials involved in the case.

The restrictions were sought after Trump falsely claimed the agents who searched his Mar-a-Lago estate for classified documents in August 2022 were prepared to kill him even though he was citing boilerplate language from standard FBI policy about use of force during the execution of search warrants. The FBI had intentionally selected a day for the search when it knew Trump and his family would be out of town, and the policy he was citing is meant to limit, rather than encourage, the use of force.

Trump's lawyers have said any speech restrictions would infringe on his free speech rights. Cannon initially rejected the prosecution's request on technical grounds, saying Smith's team had not sufficiently conferred with defense lawyers before seeking the restrictions. Prosecutors subsequently renewed the request.