The Importance of Place in Policing - Empirical Evidence and Policy ...

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The Campbell review reported noteworthy crime and disorderreductions in seven of the nine selected studies. Due to inconsistentreporting of program effects in the quasi-experimental studies, onlyrandomized trials were included in the Campbell review metaanalysis(Braga, 2005, 2007). Since all hot spots policing experimentsused citizen calls for service as an outcome measure, the maineffect size for each study was calculated based on the statistics reportedfor key calls for service findings. These effect sizes are reportedin Table 4.The effect size of the hot spots policing intervention on the treatmentplaces relative to control places was very large (2.05) and statisticallysignificant in the Jersey City Problem-Oriented Policing atViolent Places experiment. While the study reported a very largeeffect size, its influence on the overall meta-analysis was moderatedby its small sample size and correspondingly small inverse varianceweight. The Jersey City DMAP experiment intervention also had alarge statistically significant effect size (.689) and the MinneapolisHot Spots Patrol experiment intervention had a moderate statisticallysignificant effect size (.322). The Kansas City Crack HouseRaid experiment and the Minneapolis RECAP experiment at commercialaddresses had smaller non-statistically significant effect sizesthat favored the treatment places relative to the controls (.219 and.089, respectively). The Minneapolis RECAP experiment at residentialaddresses had a very small, non-statistically significant effect sizethat slightly favored the control places relative to the treatmentplaces.Since the distribution of effect sizes was found to be heterogeneous,the Campbell review used a random-effects meta-analytic modelto calculate the mean effect size for all studies. Overall, the Campbellreview found that hot spots policing interventions reduced citizencalls for service in the treatment places relative to the controlplaces (Braga, 2005, 2007). The mean effect size for the hot spotspolicing intervention for the six studies was moderate (.345) andstatistically significant. When the RECAP study was not included inthe meta-analysis due to methodological concerns, the mean effectsize was large (.632) and statistically significant.39
Table 4: Meta-Analysis of Hot Spots Experiment Effect Sizes for Main Outcomes.ExperimentEffectSizeStandardErrorInv. Var. Weight(% Total Weight)95% C.I.Jersey City POP 2.05* .504 3.93(1.8%)Jersey City DMAP .689* .275 13.21(6.0%)Minneapolis Patrol .322* .142 27.15(12.3%)Kansas City Crack .219 .139 51.32(23.3%)Minneapolis RECAPCommercialMinneapolis RECAPResidentialMeta-AnalysisAll StudiesMeta-Analysisw/o RECAP* p < .05.089 .127 62.49(28.3%)-.009 .127 62.49(28.3%)Upper 3.04Lower 1.06Upper 1.23Lower .15Upper .60Lower .044Upper .492Lower -.054Upper .337Lower -.159Upper .238Lower -.256.345* .150 Total Weight = 220.59 Upper .640Lower .058.632* .253 Total Weightw/o RECAP =95.61Upper 1.13Lower .138Since the publication of the most recent iteration of the Campbellreview, an additional randomized controlled experiment evaluatingthe crime prevention benefits of hot spots policing has been completed.In Lowell, Massachusetts, a randomized controlled experimentevaluated the effects of policing disorder, within a problemorientedpolicing framework, at crime and disorder hot spots (Braga& Bond, 2008). Thirty-four hot spots were matched into 17 pairsand one member of each pair was allocated to treatment conditionsin a randomized block field experiment. The impact evaluation revealeda statistically significant 20 percent reduction in crime anddisorder calls for service at the treatment places relative to the controlplaces. Analyses of systematic observation data also revealedsignificant reductions in social and physical disorder at the treatmentplaces relative to the control places.In sum, the empirical research is highly supportive of hot spotspolicing. Several experimental and quasi-experimental studies havedemonstrated that a focus on small high crime geographic areas canhave a positive and statistically significant impact on crime and disorder.While empirical support for hot spots policing is strong, suchapproaches would be much less useful if they simply displaced crimeto other nearby places. The issue of displacement effects is reviewedin the next section.40
Page 2 and 3: The Importance of Place inPolicingE
Page 4: ContentsForeword ..................
Page 7 and 8: eport note for example that this ne
Page 9 and 10: 8licing. By place, we do not mean l
Page 12 and 13: II. The Emergence of CrimePlaces in
Page 14 and 15: For many scholars and policymakers,
Page 16 and 17: III. The Concentration ofCrime at P
Page 18 and 19: viduals. Using his Minneapolis data
Page 20 and 21: more, Maryland using a panel design
Page 22 and 23: Figure 3: Trajectories of Individua
Page 24 and 25: V. The Importance of Place-Based Ra
Page 26 and 27: Figure 5: Kernel Density Estimation
Page 28 and 29: Perhaps the most comprehensive geog
Page 30 and 31: masked if we focused our interest o
Page 32 and 33: such places. For example, several r
Page 34 and 35: Sampson et al., 1997; Sampson, 2004
Page 36 and 37: Table 3: Relationship Between Numbe
Page 38 and 39: sas City Crack House Raids Experime
Page 42 and 43: VIII. Does Crime Just MoveAround th
Page 44 and 45: prevention effect. The Campbell sys
Page 46 and 47: know. This way, if I need help, I k
Page 48 and 49: IX. Reducing LegalConstraints while
Page 50 and 51: X. Recognizing theImportance of Pol
Page 52 and 53: esidents and business owners in hig
Page 54 and 55: demands a fundamental change in the
Page 56 and 57: concern of police to improving plac
Page 58 and 59: ReferencesAgnew R., & Peterson D. M
Page 60 and 61: Bushway, S. D., Thornberry, T. P.,
Page 62 and 63: Estricht, S., Moore, M. H., McGilli
Page 64 and 65: Mastrofski, S. M., Weisburd, D., &
Page 66 and 67: Sherman, L. W. (1990). Police crack
Page 68 and 69: Evaluating public policy initiative

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