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Ballistic Imaging (2008) / Chapter Skim
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Appendix A: Gun Enforcement and Ballistic Imaging Technology in Boston--Anthony A. Braga
Pages 291-311

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From page 293...
... Firearms examiners in the ballistics unit did not systematically compare bullets and casings from one scene to ballistics evidence recovered at other crime scenes to determine whether separate gun crimes were linked. When BPD firearms examiners did attempt to make such matches, known as making "cold hits," it happened in one of *
From page 294...
... In sharp contrast, in the pre-IBIS period, cartridges or bullets from different crimes scenes were cross-­examined by firearms examiners only in extreme circumstances or when there was a suspicion two criminal events were connected. As of December 31, 2003, the BPD ballistics unit had entered some 2,400 bullets and 12,700 cartridge casings into its imaging database and had recorded 412 confirmed IBIS-related matches. The Use of IBIS Matches in Gun Violence Prevention Strategies Confirmed IBIS matches are a key part of the BPD's gun violence reduction strategy, the Street Violence Suppression Project (SVSP)
From page 295...
... Recent IBIS matches are highlighted at the beginning of each meeting. Members of the working group discuss the circumstances associated with the linked incidents; information developed through interviews with arrested offenders, victims, and witnesses; available intelligence on current "beefs" between gangs or the activities of serious violent offenders in the linked areas and analyses of other physical evidence collected at the crime scenes, such as DNA and fingerprints.
From page 296...
... A-1.eps While ballistic imaging makes an important investigative link between two gun crime events, the availability of key information that may be critical to resolving crimes depends on random situational characteristics of the linked events. An IBIS-suggested match that links cartridge casings from shots fired from two locations with no witnesses, victims, or suspects to interview and no other physical evidence left at the scenes has low immediate potential for making arrests.
From page 297...
... Based on this pattern, the interagency working group focuses resources on gathering additional intelligence on conflicts in the area and immediately increases their presence in the area to prevent additional violence. Assessing the Value Added to Boston Gun Law Enforcement Operations by Ballistic Imaging Technology Assessment of Changes in the Productivity of the BPD Ballistics Unit To measure the effect of ballistic imaging technology on the ­productivity of the BPD ballistics unit, it is important to consider the nature of the technological innovation and its potential impact on BPD operations.
From page 298...
... examined whether IBIS changed the ability of the BPD ballistics unit to link gun crimes. To determine whether the adoption of the ballistic imaging technology was associated with a change in productivity, the annual and monthly number of cold hits made by the BPD ballistics unit was computed for the 14-year time period between 1990 and 2003. Figure A-2 presents the yearly number of cold hit ballistics matches made by the BPD ballistics unit during the study period.
From page 299...
... NOTE: Serious gun crime incidents are defined as gun-related homicides, aggra A-3.eps vated assaults, and robberies.
From page 300...
... A binary dummy variable indicating whether the IBIS technology was present or not was constructed to estimate the effects of the intervention on the monthly counts of cold hits. Negative binomial regression models, controlling for the monthly count of gun crimes, seasonal variations as measured by monthly dummy variables, and simple linear and nonlinear trends, revealed that the adoption TABLE A-1  Staffing Levels of the Boston Police Department Ballistics Unit, 1993–2003 Year Supervisors Firearms Examiners Support Staff Total 1993 1 7 1 9 1994 1 7 1 9 1995 1 7 1 9 1996 2 7 1 10 1997 2 6 2 10 1998 2 5 3 10 1999 2 6 3 11 2000 2 5 3 10 2001 2 5 3 10 2002 1 4 4 9 2003 1 5 5 11
From page 301...
... Extended Analyses of Boston IBIS Matches The Boston Police Department's Unsolved Shootings Project and Impact Player Assessment meetings held between October 2001 and July 2004 generated detailed data on gun crime incidents and gun criminals involved in IBIS matches. A total of 104 sets of ballistics matches involving 244 distinct gun crimes were made over the course of this initiative. The number of incidents in each set of matches ranged from 2 gun crimes to 6 gun crimes with a mean of 2.3 gun crimes per set.
From page 302...
... As described above, IBIS matches do not change the inherent value of ballistics evidence in an investigation because many other factors help determine whether an arrest is eventually made. An IBIS match does not guarantee an immediate arrest.
From page 303...
... Rather, matches better position law enforcement agents to identify gun criminals through strategic analyses of information and intelligence sharing. The Boston Police and their criminal justice partners use the IBIS information as a tool to shed light on the dynamics at play in violent street social networks and further their ability to apprehend violent gun criminals.
From page 304...
... The IBIS offenders were also more likely to be convicted of their gun crimes than the 1995 cohort of Boston gun offenders who had a 37 percent conviction rate for past armed violent felonies and gun possession offenses. The Use of IBIS Matches in Gun Enforcement Operations To further document the use of IBIS matches in Boston's interagency gun violence prevention efforts, available official data associated with 44 IBIS matches made by the BPD ballistics unit in 2003 (incident reports, arrest reports, intelligence reports, ATF trace data)
From page 305...
... Offenders were charged with the current offense only and not charged with a linked prior gun crime in 34.1 percent of the 44 matches. In the two matches linking homicides, the offenders were TABLE A-3  Results of Information Linked by IBIS-Suggested Matches on Investigations by Boston Law Enforcement Agencies, 2003 All   Homicide Matches Matches Direct Enforcement Actions (N = 44)
From page 306...
... While all matches were regarded as valuable by the interviewed law enforcement agents, the matches that led to an arrest clearly added the most value to gun violence prevention strategies. The 2003 investigation and arrest of a homicide suspect -- for anonymity, referred to as A -- provides a good example of the usefulness of links between crime scenes made by IBIS matches.
From page 307...
... As of December 31, 2003, the BPD ballistics unit had made a total of 404 cold hit matches involving cartridge casings using the IBIS technology. Using 2003 prices, the equipment costs amount to $730.20 per cartridge casing match. There are two reasons to believe that this cost estimate will continue to decrease markedly as time progresses: (1)
From page 308...
... Between 1995 and 2003, the Boston Police only made eight cold hit bullet matches. Using 2003 prices, the equipment costs amounts to $36,875 per bullet match.10 The benefits of IBIS to gun enforcement operations can also be assessed by estimating the number of arrests resulting from IBIS matches to the number of arrests that would have been made from traditional methods of making cold hits if the IBIS technology had not been available.
From page 309...
... According to Boston law enforcement agencies, all matches have strategic value in understanding ongoing violent conflicts among gangs and criminally active groups that are major parts of the city's violence problem. The IBIS matches, and the information chains that result from the linked gun crimes, are used to mount investigations of suspected violent gun criminals and to develop and implement violence reduction strategies to prevent additional gun crimes from happening.
From page 310...
... Attorney's Office provides the state police with $35,000 per year to support the overtime that is necessary to ensure timely ballistic imaging at the state crime laboratory. The steps of this process are as follows: • Local evidence collection: Participating police agencies must collect all evidence at gun crime scenes, which includes the collection of crime gun evidence at shots fired scenes where no injuries or fatalities are reported.
From page 311...
... APPENDIX A 311 supplemented by strategic data analyses and intelligence gathering seem to show great promise in apprehending violent gun criminals. The Boston experience with ballistic imaging technology suggest that ATF's NIBIN program, with appropriate support, can ensure that participating jurisdictions are well trained in the practices of comprehensive ballistic imaging.


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