 A <unk> caliber Charter Arms revolver , belonging to Abu @-@ Jamal , with five spent cartridges was retrieved beside him at the scene . He was wearing a shoulder holster , and Anthony Paul , the Supervisor of the Philadelphia Police Department 's firearms identification unit , testified at trial that the cartridge cases and <unk> characteristics of the weapon were consistent with bullet fragments taken from Faulkner 's body . Tests to confirm that Abu @-@ Jamal had handled and fired the weapon were not performed , as contact with arresting police and other surfaces at the scene could have compromised the forensic value of such tests . 
