Montrell Barrett, 19, lost his cool when he looked out of his third-floor bedroom window in Germantown and saw three men he suspected of having broken into his car early on March 12.
Barrett, of Logan Street near Greene, grabbed a gun and began firing at the trio, who were inside another auto, Assistant District Attorney John J. Doyle said yesterday.
Douglas Scott, 25, of Redfield Street near Haddington Avenue, was shot in the chest and died. Samuel Johnson survived gunshot wounds to his arm and leg. The third man was unhurt.