Wrongfully accused of larceny

i am accused of larceny someone stole a ps3 and stashed it in my locker that i share with THREE OTHER PEOPLE. however i am the only one getting accused because it was in my drawer inside the locker. the drawers inside the locker cant be locked. the person who stole the ps3 used his book bag and they found western union papers with his name on it so they traced it back to him. he then said that he let me borrow the bookbag a long time ago which is a lie. so i was sent to a disciplinary review board then executive officers inquery they all said that they dont need any proof to convict me of this crime and i dont think its right because there is so much reasonable doubt. so i was thinking of taking the cause to court martial correct me if im mistaking but i think they have to have proof beyond resonable doubt to find me guilty.