After a firearm has been photographed at the scene, it will be necessary to be rendered safe. An automatic pistol will require its magazine to be removed and the round extracted from the chamber. When removing the magazine it will need to be handled carefully in order to preserve potential fingerprint evidence and be placed in a paper or plastic evidence bag. The round from the chamber should be placed in a plastic vial or paper envelope. A revolver will need to have the rounds taken from the chambers within the cylinder. The chamber that is on top and in line with the barrel will need to be marked.
The cylinder and chambers should be sketched and assigned numbers. As the rounds are removed from the chambers, they need to be placed in individual plastic vials or paper envelopes with a corresponding chamber number indicated. Regardless of type, automatic or revolver, each firearm will need to have an identification tag affixed to its trigger guard. The identification tag needs to contain the hammer position, caliber, make, model and serial number of the firearm, the investigators name, date, time, and location of collection.
An additional identifier can be scratched on to the firearm, in an inconspicuous location, and in a manner that will not damage potential evidence. If the firearm was recovered from under the water’s surface, it will need to be cleared as mentioned previously, pertinent details recorded, and placed in an evidence container that will allow it to remain covered in the same water that it was found. The firearm should not be cleaned or allowed to dry.
The rounds recovered from either type of weapon will need to be packaged individually, preferably in plastic vials or paper envelopes. Each vial or envelop will need to be accompanied by the following information: date, time and location of recovery, caliber, and investigators name. If a bullet is found at the scene it should be handled carefully in order to protect the striation marks. Bullets should not be pulled out of materials that they are lodged in; the surrounding materials should be broken or chiseled away.
The bullet should be marked either on the point or the base, wrapped in tissue paper, placed in a plastic vial or envelope, and the afore mentioned information attached to the applicable evidence container. Spent shell casings, if found, should be picked up with tweezers or forceps, marked with an identifier near the mouth of the casing, packaged individually in plastic vials or envelopes, and be accompanied by the previously mentioned pertinent information. It is imperative that the chain of custody reflects the change of possession when any item is handed over to a laboratory or testing facility.