Maxx Robinson, a combat medic, shot and killed two attackers with his pistol, then treated soldiers who were wounded in the attack.
The incident left three soldiers dead and two seriously wounded.
Col. Max Moss, a spokesman for the Oklahoma National Guard, declined to comment on the case.
Maxx Robinson was awarded the Bronze Star with valor device for his actions in the battle. He also received a Purple Heart. He was discharged from the Guard in January.
Editor's note: Robinson's Afghanistan exploits were chronicled in a three-part series published last year in The Oklahoman and online here.