Eric L. Piza, E., Jason Szkola, & Kwan-Lamar Blount-Hill, K. (2021)

Policing: A Journal of Policy and Practice, 15(2): 1217-1231.

Key Takeaways

• Lack of support from leadership and mid-level managers identified as most damaging factors to police research
• Crime analysts identified as easiest to incorporate into program evaluation efforts
• Embedded criminologists identified as having the strongest research and evaluation skills
• Police pracademics identified as best equipped to explain research results to practitioners
• Overall, survey responses indicate embedded criminologists, police pracademics, and crime analysts may each have a unique (and important) role in police-led science

Research Summary

Evidence-based policing relies on rigorous program evaluation to catalog “what works” in crime control and prevention. Program evaluation has traditionally been considered the responsibility of academic researchers.  Scholars have recently called for the field to move more towards a model of police-led science, in which police are empowered to conduct research and disseminate findings throughout the field.

Three entities have emerged as potential avenues for increasing police capacity to conduct rigorous program evaluations: embedded criminologists, police pracademics, and crime analysts. Embedded criminologists are outside academic researchers who take an active role in the day-to-day routine of the police, typically spending at least a portion of their time on-site at the agency.  Police pracademics are active police officers who have received the necessary (typically graduate level) academic research training to lead research projects. Crime analysts are police department staff members who systematically analyze data to provide information to police commanders to make policing more efficient and effective.

The aim of this study was to explore the relative strengths of these three entitles in terms of increasing police capacity to conduct program evaluations. We explored these issues through a survey of scholars who authored or co-authored one or more studies included in the Evidence-Based Policing Matrix (https://cebcp.org/evidence-based-policing/the-matrix/), a research translation tool that organizes evaluations of police interventions. The survey was sent to the 146 study authors with active email addresses. 83 of the 146 (57%) authors completed the survey.

Respondents identified lack of support from police leadership and mid-level managers as the most damaging factors to police research. The two least damaging factors were lack of police personnel proficient in research and competing goals and incentive structures of academics and police.

Respondents identified crime analysts as the easiest to incorporate into program evaluation activities and embedded criminologists as the most difficult. Embedded criminologists were identified as having the strongest research ability and crime analysts the weakest. Police pracademics were identified as best able to translate research for practitioner audiences. Embedded criminologists and crime analysts were considered equally capable in this task.

Open-ended responses suggested; (1) while respondents looked at embedded criminologists positively, they were skeptical of their ability to drive internal change within police agencies; (2) police pracademics can be a driving force in research translation but may lack the technical skills to lead program evaluations; (3) crime analysts have high levels of technical expertise but may not be positioned to drive change because of their general lack of status within police agencies. The overall findings suggest embedded criminologists, police pracademics, and crime analysts each have an important, distinct role to play in police-led science. The benefits to police-led science can be maximized by expanding training opportunities for crime analysts, entrusting police pracademics to develop an agency’s research agenda, and incorporating embedded criminologists within an action research framework to expose crime analysts and police pracademics to rigorous program evaluation activities.

Eric L. Piza, Andrew P. Wheeler, Nathan T. Connealy, & Shun Q. Feng (2020)

Criminology & Public Policy, 19(2): 653-684.

*This study was funded by the Professional Staff Congress – The City University of New York.

Key Takeaways

• The Newark Police Department opened a police substation in their downtown district in 2012
• The substation had the strongest effect on motor vehicle theft, with significant reductions also observed for burglary
• Robbery and theft from auto experienced significant spatial displacement
• Quality-of-life summonses and directed police patrol significantly increased in the target area
• Parking summonses significantly decreased in the target area
• The effect of the substation was heightened when proactive policing activities increased in the target area

Research Summary

In Sept. 2012, a partnership between the Newark Police Department (NPD) and Newark Downtown District (NDD) culminated in the opening of a police substation in downtown Newark. NPD’s Metro Division uses the substation as its headquarters and has primary responsibility for policing a 0.35 square-mile target area within downtown Newark. Coinciding with the opening of the substation, the NDD increased its number of quality-of-life ambassadors, uniformed civilian personnel who travel throughout downtown Newark on foot to identify and rectify problems that may impact the community. The NDD also funded the renovation of the building space, paid the mothy rent of the substation, and added a crime analyst position to its staff to assist the NPD in tracking crime trends in the downtown area.

The microsynthetic control method (i.e. microsynth) was used to evaluate the effect of the substation on crime. Microsynth ensures the cumulative treated and control units have identical pre-intervention crime trends and are statistically equivalent across covariates that may influence crime. Microsynth measures treatment effect through a difference-in-difference estimate of post-intervention crime counts in the treated area compared to the control area.

To measure the effect of the substation over time, as well as to account for the evolving nature of the partnership, our analysis estimates effect across two distinct time periods: (1) the initial 3-year program period (Sept. 2012 – Aug. 2015) and (2) the period following the expiration of the MOU between NPD and NDD (Sept. 2015 – Aug. 2018).

We tested the effect of the substation on six crime types: aggravated assault, burglary, murder, theft from auto, motor vehicle theft, and robbery. We were also interested in identifying potential causal mechanisms of the observed findings, and included six police activities in a process evaluation: arrests, field interrogations, quality-of-life (QOL) summonses, directed police patrols, motor vehicle parking summonses, and motor vehicle moving summonses.

The strongest crime control  effects were observed for motor vehicle theft, which significantly reduced in both of the 3-year post intervention periods. Burglary also reduced during the Sept. 2012 – Aug. 2015 time period. While robbery counts in the target area did not significantly change in the postintervention period, spatial displacement effects (i.e. a significant increase in the catchment zone surrounding the target area) occurred. From Sept. 2015- Aug. 2018, the significant reduction of theft from auto in the target area was offset by a significant increase in the catchment zone. From Sept. 2015 – Aug. 2018, QOL summonses and directed patrols significantly increased, and parking summonses significantly decreased. During this same time period, the motor vehicle theft decrease nearly tripled from the Sept. 2012 – Aug. 2015 period (-88 to -252). Silver linings can also be seen in the crime increases, as the robbery increase from Sept. 2015 to Aug. 2018 (57) was less than half of the Sept. 2012 to Aug.2 015 increase (148).

The opening of NPD’s substation resulted in an increase in visible police presence accompanied by increases in proactive policing activities, which impacted motor vehicle theft and burglary. This suggest substations that facilitate proactive policing may help prevent these crime types.  Agencies wishing to address robbery and theft from auto may have to design substation strategies in a manner that better influences offender decision-making in order to prevent spatial displacement.

Eric L. Piza, Brandon C. Welsh, David P. Farrington, & Amanda L. Thomas (2019)

Criminology & Public Policy, 18(1): 135-159

*This study was funded by the Swedish National Council for Crime Prevention

Key Takeaways

• CCTV was associated with a ~13% reduction of crime in target areas as compared to control areas
• Effects were strongest in car parks followed by residential areas
• Of the countries where CCTV evaluations were conducted, the strongest effects were observed in United Kingdom and South Korea
• Schemes incorporating active camera monitoring had larger effects than passive systems
• Schemes deploying multiple interventions alongside CCTV had larger effects than schemes deploying single or no other interventions

Research Summary

This study updates prior systematic reviews and meta-analyses testing the effect of CCTV video surveillance cameras on crime. Systematic reviews incorporate rigorous and transparent methods for locating, appraising, and synthesizing scientific evidence from prior evaluation studies. Meta-analysis is a statistical technique that combines results from multiple evaluations into a single weighted average effect size.

We searched for CCTV evaluations published from 2007 through 2017 to account for the time period since the last review. The authors identified 68 CCTV evaluations from this time period. Considering these evaluations alongside those identified in the prior CCTV reviews, this study included a total of 161 CCTV evaluations conducted between 1978 and 2017.  80 evaluations met the inclusion criteria with 76 providing the necessary data for the meta-analysis.

Overall, CCTV was found to have a modest but significant effect on crime. Crime decreased by ~13% in CCTV areas as compared to control areas.

CCTV effect was compared across six geographic settings: car park (n=8), city/town center (n=33), housing complex (n=10), residential area (n=16), public transport (n=4), and other setting (n=5). The largest effects were observed for car parks, with CCTV areas experiencing a significant crime reduction of ~37% as compared to control areas. A significant reduction of ~12% was observed in residential areas as compared to control areas.

The analysis also tested whether the effect of CCTV differed across countries: United Kingdom (n=34), United States (n=24), Canada (n=6), South Korea (n=3), Sweden (n=3), Norway (n=1), Spain (n=1), Poland (n=2), and Australia (n=1). For the meta-analysis, Norway, Spain, Poland, and Australia were grouped together as “other country.” Significant reductions of approximately 21% and 34% were observed for the United Kingdom and South Korea, respectively. However, the United Kingdom findings did not lose significance when a more conservative effect size was used while the South Korea findings lost significance with the more conservative measure. Additionally, the South Korea findings warrant caution given the small number of studies conducted in this country (3) as compared to the United Kingdom (34). No other country exhibited any significant effects.

65 studies reported the type of monitoring used in CCTV schemes as active (n=54) or passive (n=11). Active systems were associated with an approximate 15% reduction in crime while no significant effects were observed for passive systems. Schemes reporting the deployment of multiple interventions (n=14) alongside CCTV generated an approximately 34% reduction of crime in treatment areas as compared with in control areas. No significant effects were observed for schemes reporting either none (n=36) or one other intervention (n=26) alongside CCTV.

The increase in CCTV evaluations has improved the knowledge base around the crime prevention effect of the technology. While overall findings suggest a modest but significant effect on crime, important geographic and strategic aspects of CCTV schemes influence the likelihood of success. Public safety agencies should take these considerations into account when designing their CCTV programs. Future research should aim to incorporate rigorous evaluation designs to ensure the policy relevance of CCTV evaluation studies. 

Eric L. Piza & Jeremy G. Carter, J. (2018)

Justice Quarterly, 35(5): 842-870

*This study was supported by the Central Indiana Community Foundation, grant # 0000018207

Key Takeaways

• Near-repeat patterns  were observed for both motor vehicle theft and residential burglary
• ~28% of motor vehicle thefts and ~37% of residential burglaries were part of a near repeat chain
• Near repeat residential burglary patterns were most salient in the 4 days following an initiator event
• Near repeat motor vehicle theft patterns were equally salient in the 4-day and 7-day periods following an initiator event
• Social disorganization and geographic edge measures predicted whether events were part of near repeat chains for both motor vehicle theft and residential burglary
• Crime generators predicted whether events were part of near repeat chains for motor vehicle theft

Research Summary

Near repeat analysis has emerged as a method for identifying clusters of crime events that occur closely in both space and time. Recent research has classified crime events based upon their role in spatiotemporal clusters and identified locations most at risk of near repeat patterns.

This study sought to identify the environmental factors that predict whether a crime event is an initiator (first event in a near repeat chain) or near repeat (subsequent event in a near repeat chain) event. Accurately forecasting, and preventing, initiator events offers enhanced crime control benefits, as additional incidents that may have occurred subsequently are also prevented.

This study used data on motor vehicle theft and residential burglary events occurring in Indianapolis, IN during 2013. For both crime types, we conducted an analysis of spatiotemporal clustering using the near repat calculator (https://www.jratcliffe.net/near-repeat-analysis). We used a spatial bandwidth of 1-block in the analysis, and repeated the analysis using 3 different temporal bandwidths: 4 days, 7 days, and 14 days.

For residential burglary, near repeat patterns were most salient in the 4-day model.  The strongest effects occurred in the 1-block band, with near repeat residential burglary patterns 78% higher than what is expected by chance. Out of the 11,536 residential burglaries, the near repeat calculator identified 2,536 (~22%) as initiator events and 1,712 (~15%) as near repeat events.

For motor vehicle theft, near repeat patterns were equally salient in the 4-day and 7-day models. The strongest effects occurred in the 1-block band with near repeat events more than 45% greater within 4-days and 53% greater within 7-days than what is expected by chance. Out of the 4,991 motor vehicle thefts, the near repeat calculator identified 802 (~16%) as initiator events and 592 (~11%) as near repeat events.

Multinomial logistic regression identified variables significantly related to the occurrence of initiator and near repeat events. For residential burglary, concentrated disadvantage, geographic mobility, housing density, and racial heterogeneity were significantly associated with an increased likelihood of a crime being a near repeat or initiator event. Proximity to railroad tracks was associated with a decreased likelihood of a residential burglary being a near repeat or initiator event while proximity to a river was associated with an increased likelihood.

For motor vehicle theft, incidents occurring in close proximity to ATMs & Banks were more likely to be near repeat or initiator events. Concentrated disadvantage, geographic mobility, housing density, and racial heterogeneity were each significantly associated with an increased likelihood of being a near repeat or initiator event. Close proximity to a river was associated with decreased likelihood of a motor vehicle theft being an initiator event.

Findings highlight the importance of spatial context to near repeat patterns. Theoretical concepts from environmental criminology play a role in understanding the occurrence of near repeat and initiator events, but in a much more nuanced manner than social disorganization theory. Overall, social disorganization measures predicted an increased likelihood of near repeat and initiator events while environmental criminology measures were associated with both increased and decreased likelihood.

David N. Hatten & Eric L. Piza (2020)

Crime & Delinquency

Study Abstract

This study investigates the temporal stability of identified near-repeat patterns using robbery crimes data in Newark, NJ. With the noteworthy exception of Hoppe & Gerell (2019) scholars have yet to explore the temporal stability of identified spatiotemporal crime clusters. Furthermore, researchers have yet to measure the near-repeat phenomenon longitudinally. To fill this gap, the current study employs a longitudinal design to measure variation in effect size and significance of identified near-repeat crime patterns across 13 “rolling” one-year time periods within a two-year study period (2015-2016). Temporal instability was found within two out of six spatiotemporal crime clusters. Results are reported in the form of formalized descriptive statistics and visualizations of temporal trends.