Forensic Services
Firearms and Tool Mark Analysis
The Firearms and Tool Marks Section is responsible for the comparison of firearms, casings, projectiles and other evidence that may be associated through tool marks. Tool marks result whenever two items come into contact with sufficient force, such that one or both of the items bear markings resulting from the other item.
The most important method utilized in Firearms and Tool Marks Section is microscopy. The comparison Microscope allows two items to be viewed simultaneously. Evidence projectiles, casings, and other items bearing tool marks are compared to known items in order to determine consistency or inconsistency, both in class characteristics and individual characteristics. In addition, the firearms section maintains a database program called NIBIN.
The NIBIN program is headed by the Bureau of Alcohol Tobacco and Firearms. This program is a success because firearms are often transported across state lines, after having been used to commit crimes. If a cartridge casing is located at a crime scene, it can be added to the NIBIN database and searched against known casings, and casings from other crimescenes. Even if the firearm used in the crime is located much later, or in another state, the firearm can be compared to the NIBIN database. Although the original cartridge casing must still be compared to the indexed firearm, the database has the ability to link serial shootings and cold cases that otherwise would have no leads.
The Firearms / Tool Marks section of the laboratory was recently relocated to the Northern Utah Crime Laboratory. This move will allow the Firearms section to grow, and has provided the Central Utah Laboratory with much needed space. Evidence can still be submitted at the Central Laboratory, as periodic transfer of evidence (between laboratories) will be maintained.