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6 Operational and Technical Enhancements to NIBIN
Pages 162-185

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From page 162...
... No program is perfect: there is always opportunity for refinement and improvement, and such is the case with NIBIN. The underlying concepts of NIBIN are sound -- facilitating transfer of information between geographically dispersed law enforcement agencies and giving those agencies access to technology that could generate investigative leads that would otherwise be impossible.
From page 163...
... The committee chair and staff attended the sixth NIBIN Users Congress meeting at FTI's U.S. training center in Largo, Florida, in October 2004.
From page 164...
... increase the nonpartner agencies' awareness and use of the system, and (3) encourage the partner agencies to promote the NIBIN program to other law enforcement agencies in their area.
From page 165...
... 12. Coordinate with Department of Justice law enforcement agencies that seize firearms and firearms evidence to help them establish a process for enter ing the seized evidence into NIBIN.
From page 166...
... 6–B  Operational Enhancements Suggesting operational enhancements to the NIBIN program is a complicated task due to the program's very nature. At its root, NIBIN is a grant-in-aid program that makes ballistic imaging technology available to law enforcement agencies to an extent that would not be possible if departments had to acquire the necessary equipment on their own.
From page 167...
... 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.
From page 168...
... In this circle, we believe that it is important that the potential for NIBIN to generate active investigative leads be the primary emphasis; to the extent that NIBIN entry is viewed as drudgery or simply "feeding the beast" to no apparent end, participation will wane. Recommendation 6.2: In order to promote wider use of NIBIN resources and to ensure that entry of ballistics evidence into NIBIN is a high ­priority, ATF should work with state and local law enforcement agencies to encourage them to incorporate ballistic imaging as a vital part of the criminal investigation process.
From page 169...
... However, other hits may be made locally (including evidence from nonpartner agencies submitting evidence to a NIBIN site) , regionally, or cross-­regionally.
From page 170...
... Recommendation 6.4: State and local law enforcement agencies should be encouraged to streamline the ballistic image acquisition process and reporting requirements as much as possible, in order to facilitate rapid data entry and avoid evidence backlogs. The California technical evaluation of a potential state reference b ­ allistic image database made reference to low levels of bullet hits achieved by the NYPD.
From page 171...
... . make hits in crimes where casing evidence is not likely to be recovered: "drive-by shootings in which the bullets are found at the scene but the casings remain in the shooter's vehicle, for example." It is impossible to fully evaluate the tradeoff between entering bullets and entering casings without a line of empirical research that is lacking at present: When both casings and ­bullets are recovered from the same scenes or collected in test firings and both are entered into NIBIN, how do relative scores and ranks on the cartridge case markings compare to those for bullets?
From page 172...
... Through such a review, it would be useful to distill "best practices" by high-achieving agencies -- for example, means of obtaining high-level commitment by agency officials, methods for working through returned lists of comparison scores, or interacting with detectives and beat officers -- for dissemination to all NIBIN partners. Recommendation 6.5: Local NIBIN experience should be a basis of research and development activities by ATF, its contractors, and the National Institute of Justice.
From page 173...
... For expedience, some agencies may only enter a single exhibit that a firearms examiner or an IBIS operator judges to be the "best" marked of the exhibits; we have observed this kind of assessment at individual law enforcement agencies, and it is also the standard practice for New York's Combined Ballistic Identification System (CoBIS) reference database when more than one casing is included as the required ballistic sample. A recurring message from the studies of IBIS performance reviewed in Chapter 4 -- as well as our committee's own experimental work, discussed in Chapter 8 -- is that ammunition type is extremely consequential in obtaining high-probability matches.
From page 174...
... Although his remarks apply specifically to the construction of a reference ballistic image database, they apply equally to NIBIN. Entry of more than one specimen per firearm, when possible, accounts for the variability inherent in firings using different ammunition makes.
From page 175...
... As ATF commented in its reply to a draft of the audit report, "consideration must be given to the availability of IBIS technology to law enforcement agencies that reside in regions that historically have low usage based on the amount of firearms crimes" (U.S. Department of Justice, Office of Inspector General, 2005:131)
From page 176...
... 6–C  Technical Enhancements Several of them deal with the specific functionality and interface of the current IBIS platform; others are broader in scope and speak to the type of information that should be recorded for the NIBIN system as a whole. Put another way, these recommendations are not a "to do" list for the current IBIS or its developers, but will require collaboration between system developers, NIBIN management, and the program's user base.
From page 177...
... and of completed hits. Even within this extremely limited set of variables, the information collected is not rich enough to answer important questions, such as whether hits are more often realized when connecting two pieces of crime scene evidence or in linking a crime scene exhibit to one test fired from a recovered weapon.
From page 178...
... We now turn to how the system could benefit from collection of a fundamental variable during the demographic entry stage of image acquisition. In our observations of IBIS at work, a major deficiency in the current set-up is the inability to specify what is known about the ammunition used in the exhibit.
From page 179...
... We do not suggest or advocate that nationwide searches against the whole NIBIN database should be routine and default, but we do concur with the Inspector General audit of NIBIN that it is important that agencies have the knowledge and training to initiate nationwide searches if conditions in a case warrant a sweeping search. It is not surprising that agencies rarely conduct national searches given that, at present, a national search must be carried out by searching each NIBIN region separately.
From page 180...
... Recommendation 6.12: Based on information from NIBIN users, ATF and its technical contractors should: • regularly review the partition structure of the NIBIN database (which defines the default search space for local agencies) for its appro priateness for partner agencies' needs, and • develop methods for flexible and user-designed searches that may be more useful to local agencies than the default partitions.
From page 181...
... Again, we do not suggest that there is necessarily anything wrong with the NIBIN program's strategy of consolidating servers at a limited number of sites, and we do not suggest that this strategy and the waiting time that it incurs is the complete, direct cause of agencies not following up comparison score results. What we do suggest is that NIBIN management must also periodically consider whether the regional server workload is balanced so that the time from image acquisition to comparison score results is as small as possible for NIBIN users.
From page 182...
... The user must be able to visually eliminate or associate candidates in order to have any level of confidence that a match is not being overlooked." We agree that users should have a clearer visual benchmark to consider when examining comparison score results, even if the actual image acquired by the system for use in deriving signatures and computing scores is different and taken under conditions most favorable to the comparison process. However, we also suggest that IBIS developers explore ways to make use of the auxiliary information collected in the side light image: Methods for computing an alternative comparison score based on the side light image should be developed and tested to see how they perform relative to the IBIS-standard methodology using the center light image.
From page 183...
... the side light image before acquiring the center light image, for easier inspection of the casing's alignment and basic features. IBIS developers should experiment with comparison scores and rankings based on the side light image, and compare those with scores using the standard center light image.
From page 184...
... Further specification of calibration and validation routines should make use of exhibits that can be entered and compared at different points in time and at different NIBIN sites, including ongoing efforts by the National Institute of Standards and Technology to develop a "standard bullet" and a "standard casing" as known measurement standards. 6–C.7  Revisiting the Comparison Process and 20 Percent Threshold Finally, we turn to a critical part of the current process: the coarse comparison pass, in which all eligible exhibits are compared with the reference exhibit using a rougher comparison score, and only the top 20 percent of scores (for any of the types of markings)
From page 185...
... We do not argue that there is anything inherently wrong with a first, coarse cut of the database or the specific method used; however, research should still be done to determine whether 20 percent is an appropriate measure, balancing gains in processing time with the potential to miss hits. We also believe that NIBIN users should have the capacity to easily adjust the threshold level in regenerating comparison score results.


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