For decades, direct comparison of bullet and cartridge case evidence has been used to link crime incidents to other crime investigations to link specific pieces of evidence to each other and to particular weapons. Since the late 1980s, emerging technology has allowed such links to be drawn between computerized images of bullets and cartridge case evidence. The development of this technology has led to speculation about its potential to generate critical investigative leads to possibly related incidents both at the local level and across broad geographic areas. A specific question that has been raised concerns the utility of a national reference ballistic image database (RBID), which would include images from test-fired rounds of most (if not all) new and imported firearms. In concept, a national RBID would permit bullet or cartridge case evidence recovered at crime scenes to be easily and rapidly linked to a firearm’s point of sale—information that is currently available only if the gun itself is recovered at the crime scene and is put through a full tracing process (see Chapter 9).
The concept of a national RBID differs from existing systems in two important ways. First, a national database of ballistic image evidence already exists, but it is not a reference database because it does not collect test firings from new weapons. In 1997, the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) formed the National Integrated Ballistic Information Network (NIBIN); as of 2005, NIBIN connects 230 law enforcement agencies, which contribute to a database of images of bullet and cartridge case evidence recovered from (or test-fired from weapons linked to) crime scenes. The NIBIN program equips agencies with Integrated Ballistics Identification System (IBIS) equipment, developed and