The legal saga of President Trump’s former national security adviser Michael Flynn continued Thursday when a judge asked the appeals court in Washington to revive his effort to scrutinize the Justice Department’s move to drop Flynn’s case.

The full U.S. Court of Appeals for the D.C. Circuit will now decide whether to take a second look at U.S. District Judge Emmet G. Sullivan’s plan to examine whether the government’s move to undo Flynn’s plea of guilty is in the public interest.

Sullivan’s request for rehearing comes after a divided three-judge panel on June 24 ordered him to put an end to the case and said Sullivan was wrong to appoint a retired federal judge to argue against the government’s position.

In response, Sullivan’s attorneys told the court that while the panel majority’s opinion is couched as a fact-bound ruling, it marks a “dramatic break from precedent” that “threatens to turn ordinary judicial process upside down.”

“It is the district court’s job to consider and rule on pending motions, even ones that seem straightforward,” wrote Sullivan’s attorneys, led by Beth A. Wilkinson. “This Court, if called upon, reviews those decisions — it does not preempt them.”

In May, Sullivan refused to grant the government’s request to end the criminal case against Flynn, who twice pleaded guilty to lying to federal agents about his contacts with Russia’s ambassador in Washington before Trump took office in 2017.

Instead, Sullivan tapped retired federal judge John Gleeson to argue against the Justice Department’s request, prompting Flynn’s attorneys to take the unusual step of asking the appeals court to intervene midstream and accusing Sullivan of bias.

Sullivan was to hold a hearing next week to scrutinize the politically charged case testing the limits of the judiciary’s power to check the executive branch.

In ruling against Sullivan in late June, appellate Judge Neomi Rao, a recent Trump nominee, found that “this is not the unusual case where a more searching inquiry is justified.”

But Judge Robert L. Wilkins disagreed, saying it was “unprecedented” for the court to shut down Sullivan’s review before he had rendered a decision. Wilkins said the judge should have an opportunity to examine the Justice Department’s change of heart.

“This is no mere about-face; it is more akin to turning around an aircraft carrier,” Wilkins, who was nominated by President Barack Obama, wrote of the government’s action.

Sullivan’s filing said the majority opinion was legally flawed for the reasons Wilkins cited. Sullivan said it was also flawed because it granted the government relief — approval of its dismissal motion — even though only Flynn and not the Justice Department petitioned the appeals court. Sullivan’s filing also said the majority relied on arguments never raised before the lower court.

“Any one” of these flaws weaken the legal standard usually required for a writ of mandamus, the type of extraordinary relief Flynn sought to shortcut the regular appeals process, Sullivan’s team argued. Such writs normally require a petitioner to show that no other remedy is available.

“Taken together, they threaten to turn mandamus into an ordinary litigation tool,” inviting “forum shopping” by parties to bypass a trial judge and run to the circuit court, Sullivan’s filing argued.

Sullivan’s attorneys also argued that the majority ignored U.S. Supreme Court and D.C. circuit court precedent allowing judges to appoint outside or amicus counsel and schedule hearings when litigating parties no longer are opposed. Sullivan’s filing also argued that the majority ignored precedent that allows the government to dismiss prosecutions only with the permission or “leave” of a trial court.

As a result, on either score, Sullivan’s team argued, Flynn failed to show a “clear and indisputable” right to immediate dismissal of his prosecution and plea of guilty. That requirement ensures that even unique, unprecedented legal questions are resolved deliberately with a full record — even if the outcome appears “potentially straightforward,” they said.

Federal appeals courts, one step below the Supreme Court, rarely agree to take a second look at cases initially decided by three-judge panels. But the D.C. Circuit recently sat as a full court to reconsider the dismissal of two lawsuits brought by House Democrats — one to enforce a congressional subpoena for Trump’s former White House counsel Donald McGahn and another challenging the president’s spending on a border wall.

Flynn was the highest-level Trump adviser convicted in special counsel Robert S. Mueller III’s Russia investigation. Instead of proceeding to sentencing, Attorney General William P. Barr ordered a review of the Flynn investigation. He then moved to drop the long-running case, saying new evidence showed FBI agents did not have a valid reason to question Flynn, so any lies he told did not amount to a crime.

The case of the retired U.S. Army general has energized Trump and his supporters who say Flynn was set up by anti-Trump investigators in the FBI. But many current and former Justice Department officials view the reversal as a troubling sign of the department’s giving in to pressure from Trump.