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Law Enforcement Use of the National Integrated Ballistic Information Network (NIBIN)

Date Published
December 8, 2013

What Is NIBIN and How Is It Used?

When a gun is made, the manufacturing equipment etches microscopic markings — somewhat like fingerprints — onto the gun’s metal parts. These markings, called tool marks, are transferred to a bullet or cartridge case when the gun is fired.

When law enforcement investigates crimes in which firearms are used, ballistic imaging of such bullets and cartridge cases can be important in solving crime.

NIBIN is a national database of digital images of spent bullets and cartridge cases that were found at crime scenes or test-fired from confiscated weapons. The Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) manages the system and provides the equipment to crime labs around the country.

A firearms examiner uses ballistic imaging to convert the spent rounds into two- or three-dimensional digital images that are uploaded into NIBIN. NIBIN can be searched for possible matches — that is, other rounds that have similar tool marks and thus may have been fired from the same gun. After a possible match, or "hit" is identified, the crime lab secures the actual spent round(s) and compares them under a microscope to confirm the hit. Then, the lab sends information on the hit (a hit report) to investigators.

A NIBIN hit report has many potential tactical and strategic uses for law enforcement. Law enforcement investigators can use it to link crimes, which can help to identify suspects. They can also use it to understand patterns of gun crime, such as gun sharing and trafficking.

Research on NIBIN

In response to an open solicitation for research on the social-science ramifications of forensic-based technologies, NIJ funded an evaluation of the operation of NIBIN.

To learn how crime investigators use NIBIN, the researchers gathered data on hits from all 150  NIBIN sites and more detailed data on hits at 19 sites around the country. The researchers also conducted a national survey of crime labs and carried out in-depth interviews with crime lab personnel and investigators at 10 NIBIN sites.

The researchers’ findings indicate that NIBIN has much untapped potential to solve crimes. Although some sites made excellent use of NIBIN and found it to be an extremely useful tool in helping to solve gun-related crime, the researchers noted that, at the time of the study, many sites were not taking full advantage of NIBIN.

The researchers determined that there was large variation between NIBIN sites — a matter of hundreds of days — in the amount of time it took to process ballistic evidence and identify hits. Long delays mean that once a hit report is sent from the crime lab to law enforcement, it might be too late to aid a particular investigation. The researchers also found that sites in areas with the most gun crime entered the most evidence into NIBIN and generated the most hits, but other sites used NIBIN very little. Regardless, hits often did not contain data, such as the location the cartridge was found, that might aid investigators. Finally, the researchers found that many investigators and prosecutors who used NIBIN hits did not provide feedback to the crime lab on how useful the hits were to their investigations — a missed opportunity to improve the system.

The researchers made numerous recommendations for improving NIBIN’s utility for crime-solving. These include ways to reduce delays in evidence processing, adding data elements to the system, and creating opportunities for training and professional development to improve the tactical and strategic value of the system.

Finally, in their executive summary, the researchers note that they briefed ATF officials on their findings at the conclusion of the study, at which time ATF outlined steps it was undertaking to improve the efficiency and effectiveness of NIBIN. The researchers added that, although “impressed” with recent progress made on the NIBIN program, "We question the sustainability of these changes, however, given the severe fiscal constraints facing ATF."

About This Article

The research described in this article was funded by NIJ award 2010-DN-BX-0001, awarded to Sam Houston State University. This article is based on the grantee report “Opening the Black Box of NIBIN: A Descriptive Process and Outcome Evaluation of the Use of NIBIN and Its Effects on Criminal Investigations, Final Report” (pdf, 116 pages).

Date Published: December 8, 2013