(CN) — Attorneys argued to the military's highest court that the judge overseeing Army Sgt. Bowe Bergdahl's court-martial should have dismissed his desertion and misbehavior charges amid criticism from Sen. John McCain.
Eugene Fidell, Bergdahl's civilian attorney, filed a petition for a writ of mandamus on Wednesday asking the U.S. Court of Appeals for the Armed Forces to throw out the charges, or limit the punishment.
He says in the petition that McCain's public comments describing Bergdahl as "clearly a deserter" were "flagrantly illegal interference by the single most powerful member of the Senate Armed Services Committee."
McCain, who chairs the committee, had also vowed to hold a hearing if Bergdahl was not punished.
"It is difficult to imagine a more blatant threat to the fair administration of military justice than the one Sen. McCain uttered," the petition states.
Bergdahl, 30, was immediately captured and spent five years as a Taliban prisoner after walking away from his combat outpost in Afghanistan in 2009. His release came only after the White House agreed to swap five Taliban detainees being held at Guantanamo Bay.
He was charged with desertion and misbehavior before the enemy for walking away from his post in Afghanistan's Paktika province.
Bergdahl's trial is still scheduled for Feb. 6 at Fort Bragg, but Army prosecutors asked for a delay until May while they work to gather some 6,000 classified documents.
Fidell also expressed doubt Wednesday that the soldier could receive a fair trial under a Donald Trump presidency. The president-elect denounced Bergdahl as a "dirty, rotten traitor" while campaigning in New Hampshire in August.
His next motion hearing is scheduled for Monday at the Fort Bragg courtroom on post.
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