Col. Gregory Gross says other defendants previously have been ordered to shave. He filed a response Wednesday with the U.S. Court of Appeals for the Armed Forces.
Last week that court delayed Maj. Nidal Hasan's upcoming court-martial while it considers his objection to being forcibly shaved.
The Army prohibits beards but Hasan has grown one to express his Muslim faith. Gross has banned Hasan from courtroom hearings, but said he will be forcibly shaved before the trial if he doesn't shave himself.
Hasan faces the death penalty if convicted in the attack on the Texas Army post that killed 13.