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During a pretrial hearing Monday, a military judge called harsh comments President Trump made about Army Sgt. Bowe Bergdahl while campaigning "disturbing."

Bergdahl walked away from his post in Afghanistan in 2009, and has said he did so because he wanted to bring attention to what he saw as problems with his unit. He was held captive by the Taliban before being exchanged for five of the militant group's prisoners in May 2014. During the hearing at Fort Bragg, North Carolina, defense attorneys played a five-minute video that showed Trump calling Bergdahl a "traitor," a "no-good traitor," and other names more than 40 times. They argued that Bergdahl's due-process rights have been violated and the case should be dismissed, The Associated Press reports. The judge, Army Col. Jeffery Nance, called the video "disturbing material," and is expected to soon release his written decision on the defense's request.

Prosecutors say that Trump only made his comments as a way to "attack a political opponent for political gain," but Bergdahl's defense attorney, Eugene Fidell, said that because Trump has kept other campaign promises, what he said on the trail must not be waved away as rhetoric. An Idaho native, Bergdahl is now working a desk job at an army base in Texas, and is charged with desertion and misbehavior before the enemy, which carries a maximum penalty of life in prison.