No spent casings on the roof
Evidence Corroborated Circumstantial Official copy physical
Bagley found none on first look. Information: one spent round still in the recovered bolt-action, three unfired. Consistent with a bolt gun, not an auto-loader dumping brass on gravel.
Absence of roof brass is a weapon-class clue. It is not by itself the shooter’s name. Hull later said an unfired round on a different roof was an officer ejecting a rifle cartridge.