The federal judge in the Michael Flynn case is asking an appeals court to rethink its decision ordering the charges against the former national security adviser to be dropped.

Judge Emmet Sullivan, of the district court in D.C., filed a petition with the D.C. Circuit Court of Appeals to rehear the case after a three-judge panel ordered him to allow the Department of Justice (DOJ) to withdraw its case.

"The panel’s decision threatens to turn ordinary judicial process upside down," Sullivan's attorney wrote in the petition. "It is the district court’s job to consider and rule on pending motions, even ones that seem straightforward. This Court, if called upon, reviews those decisions — it does not preempt them."

In a move that surprised many, the DOJ in May moved to drop its case that Flynn had lied to the FBI, even though he had already pleaded guilty to the charge.

Sullivan decided to explore the legal questions around the unusual move and appointed an outside counsel to present a counterargument to the DOJ's motion.

Flynn's lawyers asked the D.C. Circuit to intervene and force Sullivan to grant the motion in what's known as a mandamus petition — a legal maneuver asking an appeals court to issue a command to a lower court.

A three-judge circuit panel ruled 2-1 last month that Sullivan did not have the authority to second-guess the DOJ's decision to drop charges. Both judges in the majority were Republican appointees, overruling an Obama-appointed judge who dissented.

"In this case, the district court’s actions will result in specific harms to the exercise of the Executive Branch’s exclusive prosecutorial power," Judge Neomi Rao, who was appointed by President Trump, wrote in the majority opinion.

"If evidence comes to light calling into question the integrity or purpose of an underlying criminal investigation, the Executive Branch must have the authority to decide that further prosecution is not in the interest of justice," Rao added.

Sullivan is now asking the D.C. Circuit to rehear the case, which would involve a broader panel of judges weighing the arguments. A majority of the circuit's 11 judges are needed to approve a rehearing.

He argued that the panel decision erred in not allowing him to hold a hearing on whether to grant the DOJ's motion, let alone rule on it.

"Judicial decisions are supposed to be based on the record before the court, not speculation about what the future may hold," Sullivan's lawyer wrote. "All the district court has done is ensure adversarial briefing and an opportunity to ask questions about a pending motion. Outside the panel opinion, those actions have not been considered inappropriate — much less an extreme separation-of-powers violation justifying mandamus."

--Updated at 3:50 p.m.