SHORT STORY: Officers responded to an ADW in progress three suspects in possession of handguns. As they arrived, they received word that one of the suspects had run into a market. The officers surrounded the market. Officer E removed the shotgun from its rack and chambered a round. He loaded a round into the shotgun from the butt-cuff. He took the safety off and placed his finger along the frame because he felt that the armed suspect may come out of the building shooting (a rear door was open). While re-positioning himself, he slipped. As he attempted to regain his balance, his finger wrapped around the trigger and he had an unintentional discharge into the ground. BOPC FINDING: AD on Unintentional Discharge: Operator error. Violation of Department’s Basic Firearm Safety Rules.