Firearms and Toolmarks
Sometimes incorrectly referred to as ballistics, firearms identification can be defined as: The identification of fired bullets, cartridge cases, or other ammunition components as having been fired from a specific firearm.
Firearms identification is actually a form of Toolmark Identification where the firearm, because it is made of a material harder than the ammunition components, acts as a tool to leave impressed or striated marks on the various ammunition components that come into contact with the firearm.
Firearms evidence submitted to a lab's Firearms/Toolmark Section will typically include a firearm, fired bullets, spent cartridge cases, spent shot shells, shot, shot shell wadding, live ammunition, clothing, and occasionally other types of items like doors, wall sections, beds, mattresses, etc.
In addition to comparing ammunition components to firearms, firearm/toolmark examiners conduct other examinations that usually include the following:
- Testing firearms to determine if they function properly
- Examine clothing and other items for gunshot residues and/or shot patterns in an attempt to determine a muzzle-to-garment distance
- Determine the caliber and manufacturer of ammunition components. Including the examination of various shot shell components
- Determine the manufacturer or manufacturers of firearms that may have fired a particular bullet or cartridge case
- Compare tools to toolmarks left on different types of items/material in an attempt to identify the tool working surface that may have been used in the commission of the crime
- Altered and obliterated serial number restorations on firearms and other metal objects
- Crime scene response and shooting incident reconstructions including autopsy proceedings
Firearm/toolmark examiners will perform specific scientific examinations upon the evidence submitted. Once the examinations are completed, reports detailing their findings are forwarded to the investigating officer and eventually to all parties involved in any subsequent criminal proceedings.
Firearm examiners finish their involvement of a case by presenting their findings in a court of law.
NIBIN (National Integrated Ballistics Information Network)
The SDFL's firearms section participates with the ATF's National Integrated Ballistics Information Network (NIBIN). NIBIN is a networked, computer database of fired cartridge casing and bullet images for forensic laboratories. NIBIN was developed to assist firearm examiners link criminal activity and solve open firearm cases by allowing the comparison of evidence with fired bullets, cartridge casings, shotgun casings, and firearms recovered in other cities and states.
The types of cases that should be entered into the system would be:
- Shootings that have the potential of being serial in nature, such as homicides, gang-type shootings, drive-by shootings, drug-related shootings, and robberies.
- Firearms confiscated from Interstate travelers, known gang members, and drug users and dealers should be test-fired and entered into the system.
To learn more about NIBIN or to make arrangements to have evidence or firearms entered and searched in the database, contact the evidence section of the SD Forensic Lab (605) 773-7843.