vidual specimens recovered as evidence from crime scenes. Recommendation 7 of the Inspector General audit of NIBIN (U.S. Department of Justice, Office of Inspector General, 2005) urges a general reconsideration of the imaging of bullets, motivated by survey responses from agencies about why they do not enter bullet evidence. Reasons cited for not entering bullets into NIBIN included the time-consuming and difficult nature of acquiring bullets, as well as a perceived low probability of success in generating hits. It has also become common practice by NIBIN users to acquire only firing pin and breech face images from cartridge casings and not the ejector marks when those are available. From observations of NIBIN sites, this seems to be largely due to the added time required to acquire that image (free-hand tracing of the region of interest), even though some research described in Section 4–E documents increased chances of generating hits when all three images are collected.

Understanding that decisions on entry priorities must be made at the local level, as determined by available resources, we suggest one basic ordering.

Recommendation 6.1: In managing evidence entry workload, NIBIN partner sites should give highest priority to entering cartridge casings collected from crime scenes, followed by bullet evidence recovered from crime scenes.

This recommendation is based in part on the findings of our study of completed hits in 1 year’s worth of operational data from NIBIN; evidence suggests that the prompt acquisition and processing of cartridge case evidence results in the greatest number of hits. We do not discount the importance of the hits that arise from the entry of specimens test fired from firearms recovered by the police; links drawn to past cases (and past crimes) can be very useful in effective prosecution of criminal suspects. However, we believe that the system’s greatest benefit may come from its use as a tool for working with active, open case files, generating investigative leads that may lead to the apprehension of at-large suspects rather than confirming other offenses associated with a gun (and suspect) already in police custody.

Though our committee’s focus on a national reference ballistic image database has led us to focus more on the imaging of cartridge cases than bullets, we give the entry of evidence bullets a slight edge in priority over the entry of nonevidence (test-fired) cartridge casings. This again favors emphasizing the use of NIBIN in the most active crime investigations. However, this choice will ultimately be contingent on continuing improvements to the technology, streamlining the image acquisition process and improving comparison results for bullets. (We discuss related concerns

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