Lawyers for Sgt. Bowe Bergdahl believe the judge overseeing the court-martial should have dismissed the desertion and misbehavior charges amid criticism from Sen. John McCain -- and are calling on the military's highest court to intervene. Eugene Fidell, Bergdahl's lawyer, filed a writ of mandamus on Wednesday calling on the U.S. Army Court of Appeals for the Armed Forces to toss out the charges. Bergdahl's lawyers filed a similar petition to the U.S. Army Court of Criminal Appeals last month, which has not been resolved. "This original mandamus petition raises an important question that directly implicates public confidence in the administration of justice: is it lawful for the chairman of the Senate Armed Services Committee to publicly brand a specific accused as 'clearly' guilty of a serious offense and threaten to conduct a hearing if he is not punished at a court-martial?" according to the writ. Bergdahl walked off a remote post in Afghanistan in 2009 and was subsequently held by the Taliban for nearly five years. He was released in May 2014 in exchange for prisoners being held at the U.S. military prison at Guantanamo Bay, Cuba. Bergdahl has said he left the base to catch the attention of military brass. He wanted to warn them about what he believed were serious problems with leadership in his unit. His court-martial is scheduled for Feb. 6 at Fort Bragg. McCain, chairman of the Senate Armed Services Committee since January 2015, has repeatedly made comments about the case and indicated that if the military justice system doesn't punish Bergdahl, the committee will hold a hearing. Fidell has accused McCain of exerting influence in the case. In August, Bergdahl's lawyers filed a motion for oral arguments to dismiss charges because they don't believe Bergdahl can receive a fair trial in light of McCain's comments. They said if Col. Jeffrey Nance, the judge overseeing the court-martial, wouldn't dismiss the case, he should limit Bergdahl's sentence to no punishment. Nance denied the request. In October, Berdahl's lawyers filed a motion asking the U.S. Army Court of Criminal Appeals to intervene. That motion hadn't been resolved by the time the lawyers filed a motion to the military's highest court. Information from the Associated Press was used in this report.