Crime Displacement Research Articles

Crime displacement: what we know, what we don’t know, and what it means for crime reduction

If offending were simply displaced following (often spatially) focused crime reduction initiatives, the continued expenditure of resources on this approach to crime reduction would be pointless. The aims of this article were to: critically appraise the current body of displacement research; identify gaps in understanding; articulate an agenda for future research; and to consider the implications of the accumulated findings for practitioners, evaluators, and policy makers. First, we review existing criminological theory regarding crime displacement and the alternative perspective—that crime prevention activity might generate a diffusion of crime control benefits. Second, we review the empirical research, focusing in particular on the findings of existing systematic reviews. Third, we consider the types of displacement that might occur and the methodological approaches employed to study them. Theoretical and empirical research suggests that displacement is far from inevitable and that a diffusion of crime control benefit is at least as likely. However, some forms of displacement have not been adequately studied. Existing research suggests that successful crime reduction interventions often have a positive impact on crime that extends beyond the direct recipients of a particular project. However, current understanding of crime displacement and how benefits might diffuse remains incomplete. Consequently, to inform an agenda for future research, we derive a typology of methodological issues associated with studying displacement, along with suggestions as to how they might be addressed.

Displacement of crime and diffusion of crime control benefits in large-scale geographic areas: a systematic review

To conduct a systematic review examining the extent to which there is crime displacement or a diffusion of crime control benefits in social control interventions implemented in medium sized or large geographic areas. A number of search strategies were used to identify and code eligible experimental or quasi-experimental studies that measured displacement in areas larger than crime hot spots. A total of 33 publications covering 43 quasi-experimental studies were identified as eligible. Nineteen of these publications covering 20 studies were included in a meta-analysis. The narrative results overall suggest that displacement is not a common occurrence in interventions implemented at larger units of geography and a diffusion of crime control benefits is somewhat more likely to occur. The effect sizes from the meta-analyses suggest that, while the interventions, on average, were associated with a significant decline in crime, displacement was not likely to occur. The meta-analyses found no significant overall evidence of displacement or a diffusion of benefits. These findings are in line with previous reviews that have focused on displacement at smaller geographic units. When examining larger geographic scales and a broader array of interventions, spatial displacement is still a fairly unlikely occurrence.

THE EFFECTS OF DIRECTED PATROL AND SELF‐INITIATED ENFORCEMENT ON FIREARM VIOLENCE: A RANDOMIZED CONTROLLED STUDY OF HOT SPOT POLICING

Targeted policing has proven effective in reducing serious crime in areas where it is highly concentrated, but the enforcement mechanisms responsible for the success of so‐called hot spots strategies remain poorly understood. This study evaluates the effects of a 9‐month randomized controlled hot spots field experiment on firearm assaults and robberies in St. Louis, Missouri. Thirty‐two firearm violence hot spots were randomly allocated to two treatment conditions and a control condition. Directed patrols were increased in both treatment conditions, whereas the experimental protocol limited other enforcement activity in one of the treatment conditions and increased it in the other. The results from difference‐in‐difference regression analyses indicate that the intervention substantially reduced the incidence of nondomestic firearm assaults, with no evident crime displacement to surrounding areas, to times when the intervention was not active, or to nonfirearm assaults. By contrast, we find no effects of the intervention on firearm robberies. Less definitive results suggest that the certainty of arrests and occupied vehicle checks account for the treatment effects on nondomestic firearm assaults.

Entertainment as Crime Prevention: Evidence from Chicago Sports Games

The concern that mass media may be responsible for aggressive and criminal behavior is widespread. Comparatively little consideration has been given to its potential diversionary function. This paper contributes to the emerging body of literature on entertainment as a determinant of crime by analyzing Chicago by-the-minute crime reports during major sporting events. Sports provide an exogenous infusion of TV diversion that we leverage to test the effect of entertainment on crime. Because the scheduling of a sporting event should be random with respect to crime within a given month, day of the week, and time, we use month-time-day-of-week fixed effects to estimate the effect of the sporting events on crime. We compare crime reports by the half hour when Chicago’s NFL, NBA, or MLB teams are playing to crime reports at the same time, day, and month when the teams are not playing. We conduct the same analysis for the Super Bowl, NBA Finals, and MLB World Series. The Super Bowl generates the most dramatic declines: total crime reports decrease by approximately 25 percent (roughly 60 fewer crimes). The decline is partially offset by an increase in crime before the game, most notably in drug and prostitution reports, and an uptick in reports of violent crime immediately after the game. Crime during Chicago Bears Monday night football games is roughly 15 percent lower (30 fewer crimes) than during the same time on non-game nights. Our results show similar but smaller effects for NBA and MLB games. Except for the Super Bowl, we find little evidence for temporal crime displacement before or after the games. In general, we find substantial declines during games across crime types – property, violent, drug, and other – with the largest reductions for drug crime. We believe fewer potential offenders on the streets largely explain the declines in crime.

Analyzing Crime Displacement with a Simulation Approach

Crime tends to cluster in small areas. Police have taken advantage of this by identifying these ‘hotspots' of crime and concentrating their resources in these locations. This practice has shown evidence of reducing crime in the hotspot area. While it is possible that the benefits of such reduction might be diffused to the surrounding areas, one criticism of this practice is that the crime in the hotspot may also be displaced to the surrounding areas. A number of empirical studies have investigated the spatial pattern of crime displacement. However, few have attempted to uncover the mechanisms that lead to the displacement of crime. In this paper we present a theory-driven approach that applies agent-based modeling to simulate the mechanism of crime and policing. The processes that drive possible displacement of crime are investigated through experiments in a computational laboratory—SPACES. Our results reveal that crime cannot be displaced easily because opportunities for crime are limited in low-crime areas and offenders are often attached to the area where they perform their routine activities.

Migrant Sex Workers: An Analysis of Transnational Crime Displacement and Antitrafficking Measures

The objective of this study is to examine South Korea’s nationwide antitrafficking measures that were implemented after the introduction of the Act on the Punishment of Intermediating in the Sex Trade, which has resulted in transnational crime displacement. The paper introduces the transnational crime displacement phenomenon in human trafficking and smuggling for sexual exploitation. It reviews transnational crime displacement cases in the areas of drug trafficking, terrorism, and the sex trade. Following this is a discussion about the data source and its findings: the secondary data analysis of a survey of 1,078 Korean sex workers. The results are mixed, but multivariate logistic regression series do support that transnational crime displacement in the sex trade and human trafficking occurred after the nationwide antitrafficking efforts in South Korea. Finally, the authors discuss the implications for theory and policy so as to improve our understanding of transnational crime displacement, the current antitrafficking policy, and of control efforts from an international perspective.

Police Foot Patrol and Crime Displacement

Police patrol, motorized and foot, has a long history of being used as a crime prevention method. Scientific evaluations of this crime prevention technique have been undertaken for at least 40 years, with mixed results. One of the important questions to be answered regarding the implementation of a police patrol is the presence of crime displacement: criminal activity simply moving around the corner, away from the primary patrol area. Previous investigations of this phenomenon have found that, most often, crime displacement is nonexistent or less than crime reductions in the primary area of interest. In this article, we investigate local crime displacement. We use a spatial point pattern test that can identify changes in the spatial patterns/distribution of crime even if crime in all areas has decreased. We find moderate evidence for the presence of this spatial shift and discuss the implications.

Boundary Adherence during Place-based Policing Evaluations

Objectives: This note explores complications with standard methods to evaluate place-based policing interventions. It identifies and explains issues of boundary misspecification during evaluation as a result of boundary adjustment by police during an intervention. Method: Using geographic data gathered during post-experiment focus groups with officers involved in the Philadelphia Foot Patrol Experiment, we highlight the practice of boundary adjustment on the part of officers and we explain why such adjustments occurred. Results: Officers involved in the focus groups who identified the active boundaries of their hot spot assignments ( n = 124) all reported policing outside of their delineated beats. On average, their active beats were 0.13 square miles larger than the originally delineated treatment beats. Some active beats overlapped catchment and control locations. Conclusion: Boundary misspecification could cause researchers to (1) incorrectly label a direct benefit of receiving treatment as a diffusion of crime control benefits; (2) underestimate immediate spatial crime displacement; and (3) underestimate treatment effects. Future place-based experiments should take into account the various pressures on officers to adjust the boundaries of their assignments by incorporating measures that track boundary adherence over time (and reporting them) in order to optimize assessments of net effects, diffusion and displacement.

A Review of Research on Crime Displacement Theory

Reppetto (1976) published crime displacement theory in Journal of Research in Crime and Delinquency and put forward his theoretical underpinnings for the future analysis of crime displacement phenomenon and outlined five types of crime displacement such as: 1. Temporal - Committing the intended crime at a different time; 2. Tactical - Committing the intended crime in a different way; 3. Target - Committing the intended crime type on a different target; 4. Spatial - Committing the intended crime type to the same target in a different place; 5. Functional - Committing a different type of crime. Research on crime displacement began to be carried out in a more systematic manner during the 1990s. There was a significant step forward when research in 1990 and 1993 specifically studied displacement and found it to be much less of problem than had generally been supposed. Crime displacement occurred where it was most likely to be similar targets or to similar and adjacent areas. Although the findings were greatly positive, there was and not surprisingly, variation between different crimes. Research has consistently found that crime displacement is the exception rather than the rule and that diffusion of benefits is just as likely and sometimes more likely to occur. Research also shows that crime displacement is unlikely in the aftermath of broader community development programs. In cases where some displacement occurs it tends to be less than the gains achieved by the response and found that crime displacement and diffusion are equally likely to occur. The theory of crime displacement is related to rational choice theory and there are three assumptions regarding the potential perpetrator and the target. The theory of crime displacement does not explain the reason of perpetrators committing a certain crime or why some crimes are more attractive to them than others. Crime displacement can occur in different ways or methods. An often-stated opinion about crime displacement is the theory, its practical usages, that it can induce a sense of disbelief towards crime prevention initiatives.

A Contribution to the Study of Geographical Displacement of Crime using GIS–Kings Cross, London

Displacement of crime is the specter that haunts crime prevention studies, in that, the crime problem does not go away but shifts from one location to another. The fact that crime is not reduced in an area but rather moves around means that trying to change the situation and circumstances surrounding the targeted area may not fully reduce crime. Research that has been previously carried out into the study of geographic displacement of crime in the Kings Cross area did not have any spatial element within the methodology. Most analyses have used more statistical methods than spatial analysis. This research aimed at investigating how the patterns of prostitution, “arrests for soliciting”, have changed between June 2000 and May 2005, more specifically to find out whether there had been a “displacement of crime” or a “diffusion of benefits.” This research used a geographical information system and a general statistical method to investigate how much, and in which direction(s) crime had been displaced. It also explored the temporal nature of offences within the study area. Data provided on offenders also included, apart from the locational information, the date and time of the offences. Analysis was also carried out to establish how “arrests for soliciting” changed overtime in Camden Basic Command Unit (BCU) . The hotspot analysis using kernel density estimation (KDE) revealed that there had been a significant displacement of crime events to the north of the target area. The hotspots revealed a “displacement of crime” in a north-easterly direction; it is interesting to know that the resultant index of displacement for a buffer zone of 500 m around the target area varied over the years. It can be shown from the research that between the periods of June 2000 and May 2005 there were varied relationships between diffusion and direct effects. The most recent weighted displacement quotient (WDQ) indicates a positive net effect of the program in May 2005. As part of the temporal analysis on average between June 2000 and May 2005, most of the “arrests for soliciting were made during a week day, specifically during the midweek. The least number of “arrests for soliciting” occurred during the weekends and Mondays. Keywords: GIS, crime displacement, hotspot analysis, index of displacement, temporal analysis

Deterrence and Geographical Externalities in Auto Theft

Understanding the degree of geographical crime displacement is crucial for the design of crime prevention policies. This paper documents changes in automobile theft risk that were generated by the plausibly exogenous introduction of Lojack, a highly effective stolen vehicle recovery device, into a number of new Ford car models in some Mexican states, but not others. Lojack-equipped vehicles in Lojack-coverage states experienced a 48 percent reduction in theft risk due to deterrence effects. However, 18 percent of the reduction in thefts was displaced toward unprotected Lojack models in non-Lojack states, providing new evidence of geographical crime displacement in auto theft. (JEL H76, H77, K42, O17, O18, R23)

An evaluation of police foot patrol in Lower Lonsdale, British Columbia

A crime reduction initiative of increased police foot patrol was implemented in a relatively low-crime community, 09 June 2010–30 September 2010. This study analyzes police incident data from January 2007 to September 2010 to evaluate this initiative. Overall, there was a drop in calls for police service in 2010, 16–17%. Moreover, the results of the evaluation indicate a statistically significant reduction in mischief and commercial burglary. The results also suggest that increasing police foot patrol does not lead to crime displacement. Overall, this evaluation adds to the police foot patrol literature by showing that police foot patrol does have a positive effect on crime in relatively low-crime areas and on property crimes.

The minimum dropout age and student victimization

Over the years, the minimum dropout age has been raised to 18 in 21 states. Although these policy changes are promoted for their educational benefits, they have been shown to reduce crimes committed by youths in the affected age groups. However, an unintended consequence of increasing the minimum dropout age could be the displacement of crime from the streets to schools. We use data from the Youth Risk Behavior Surveys to estimate the relationship between minimum dropout age laws and student victimization. Our results suggest that higher minimum dropout ages increase the likelihood that females and younger students report missing school for fear of their safety and younger students are more likely to report being threatened or injured with a weapon on school property. Our results also yield some evidence that students are more likely to report being victims of in-school theft when the minimum dropout age is higher.

CCTV and crime displacement: A quasi-experimental evaluation

The installation of CCTV cameras in the historic centre of Malaga in March 2007 was the main crime prevention initiative implemented in the city during the past few years. This was one of the first multi-camera CCTV installations on streets in Spain, which is why a proper evaluation of its effectiveness is so important for the future use of such cameras. Using a quasi-experimental design with a pre/post test, we collected data from interviews with CCTV operators, police officers and local authority officials and from surveys of pedestrians and shopkeepers. The team also examined police crime data and CCTV incident data. In this paper we will discuss the results in terms of the following three hypotheses relating to crime reduction, displacement and public security: (a) the use of cameras reduces the levels of crime, whether property crime (robberies and burglaries), crimes against people or both; (b) some of those crimes are displaced to nearby areas within or close to the city centre where there is no camera coverage but where there are similar opportunities to commit crimes; and (c) people claim to feel safer in the city centre after dark after the cameras were introduced.

A randomized test of initial and residual deterrence from directed patrols and use of license plate readers at crime hot spots

To test the effects of short-term police patrol operations using license plate readers (LPRs) on crime and disorder at crime hot spots in Mesa, Arizona. The study employed a randomized experimental design. For 15 successive 2-week periods, a four-officer squad conducted short daily operations to detect stolen and other vehicles of interest at randomly selected hot spot road segments at varying times of day. Based on random assignment, the unit operated with LPRs on some routes and conducted extensive manual checks of license plates on others. Using random effects panel models, we examined the impact of these operations on violent, property, drug, disorder, and auto theft offenses as measured by calls for service. Compared to control conditions with standard patrol strategies, the LPR locations had reductions in calls for drug offenses that lasted for at least several weeks beyond the intervention, while the non-LPR, manual check locations exhibited briefer reductions in calls regarding person offenses and auto theft. There were also indications of crime displacement associated with some offenses, particularly drug offenses. The findings suggest that use of LPRs can reduce certain types of offenses at hot spots and that rotation of short-term LPR operations across hot spots may be an effective way for police agencies to employ small numbers of LPR devices. More generally, the results also provide some support for Sherman’s (1990) crackdown theory, which suggests that police can improve their effectiveness in preventing crime through frequent rotation of short-term crackdowns across targets, as it applies to hot spot policing.

The Minimum Dropout Age and Student Victimization

Over the years, the legal minimum dropout age has been raised to 18 in 21 states. Although these policy changes are often promoted for their educational benefits, they have also been shown to reduce crimes committed by youths in the affected age groups. However, an unintended consequence of increasing the minimum dropout age could be the displacement of crime and delinquency from the streets to schools. To examine this issue, we use data from the national Youth Risk Behavior Surveys to estimate the relationship between minimum dropout age laws and student victimization. Our results suggest that higher minimum dropout ages increase the likelihood that females and younger students report missing days of school for fear of their safety and that younger students are more likely to report being threatened or injured with a weapon on school property. Our results also yield some evidence that students are more likely to report being victims of in-school theft when the minimum dropout age is higher.

Looking for displacement effects: exploring the case of ecstasy and amphetamine in the Netherlands

This article assesses the role of crime displacement within organized crime, taking the Dutch synthetic drugs market as a case study. Since the late 1990s, the policy of the Dutch government has focused on raising barriers to synthetic drugs producers in obtaining precursors and other essential chemicals. The reason is simple. Without these chemicals there would be no synthetic drugs. Over the years, this policy has resulted in a scarcity of the main ingredients for synthetic drugs. But how have criminal organizations responded to this scarcity? Can displacement effects be identified and can they be attributed to specific prevention measures? The answer is a partial yes. Yes, crime displacement can be identified in organized crime. However, measuring the precise effects remains complex.

Getting deterrence right?

In recent years, scholars have begun to argue that police interventions provide an effective approach for gaining both special and general deterrence against crime. A series of experimental and quasi-experimental studies has shown that the police can be effective in preventing crime (Braga, 2001, 2005; Skogan and Frydl, 2004; Weisburd and Eck, 2004), and that such crime prevention benefits are not offset by displacement of crime to areas near to police interventions (Braga, 2001; Weisburd et al., 2006). Durlauf and Nagin (2011: 14) drew from this literature to argue that, “Increasing the visibility of the police by hiring more officers and by allocating existing officers in ways that heighten the perceived risk of apprehension consistently seem to have substantial marginal deterrent effects.” Indeed, they concluded that crime prevention in the United States would be improved by shifting resources from imprisonment to policing. A recent innovation in policing that capitalizes on the growing evidence of the effectiveness of police deterrence strategies is the “focused deterrence” framework, which is often referred to as “pulling-levers policing” (Kennedy, 1998, 2008). Pioneered in Boston as a problem-oriented policing project to halt serious gang violence during the 1990s (Braga, Kennedy, Waring, and Piehl, 2001), the focused deterrence framework has been applied in many U.S. cities through federally sponsored violence-prevention programs such as the Strategic Alternatives to Community Safety Initiative and Project Safe Neighborhoods (PSN) (Dalton, 2002). Focused deterrence strategies honor core deterrence ideas, such as increasing risks faced by offenders, while finding new and creative ways of deploying

Measuring the crime displacement and diffusion of benefit effects of open-street CCTV in South Korea

Crime prevention strategies are implemented to reduce the damage caused by crimes with CCTV (Closed-Circuit Television) being broadly accepted as one of the main strategies. However, along with CCTV's perceived high expectations as crime deterrent, there is also a growing controversy over CCTV's potentially unexpected limitations. For example, the crime displacement (the presence of CCTV will change the locations of crime and its total number will not change) and the diffusion effects of crime control benefits (the crime prevention effect of CCTV may filter through to neighboring areas) are the representative controversial issues. In this study, we aimed to verify the crime displacement and the diffusion of benefit of open-street CCTV by analyzing the crime tendencies empirically.Gwang Myeong City in Gyeonggi Province, South Korea was chosen to analyze the crime displacement using the WDQ (Weighted Displacement Quotient) which compares the crime tendency of a location with that of its neighboring areas. The results showed that the crime prevention effect of the CCTV was significant. The number of robberies and thefts in the areas with CCTV installed reduced by 47.4%, while the areas without CCTV showed practically no change in the number of crimes. The crime displacement caused by the CCTV was not either found or inconsequential, and the crime rates in the neighboring areas also decreased slightly. Of major cause for concern was the fact that CCTV was marginally effective in deterring violence and as such, there should be a more detailed scientific analysis of the pattern and type of crimes committed in an area where CCTV's are being installed.

Police strategies to reduce illegal possession and carrying of firearms: effects on gun crime

This Campbell systematic review examines the impacts of police strategies to reduce illegal possession and carrying of firearms on gun crime. Examples include gun detection patrols in high‐crime areas, enhanced surveillance of probationers and parolees, weapon reporting hotlines, consent searches, and other similar tactics.Four studies met the inclusion criteria, reporting a total of seven non‐randomized tests of directed patrols focused on gun carrying in three American cities (five tests) and two Colombian cities (two tests).These studies suggest that directed patrols focused on illegal gun carrying prevent gun crimes. However, conclusions and generalizations must be qualified based on the small number of studies, variability in study design and analytic strategy across the studies, pre‐intervention differences between intervention and comparison areas, and limited data regarding factors such as implementation, crime displacement, and long‐term impact. There is also a strong need for rigorous study of other strategies to reduce illegal possession and carrying of firearms.Executive summary/AbstractBACKGROUNDCriminal misuse of firearms is among the world's most serious crime problems. Strategies to reduce gun violence include efforts to restrict the manufacture and sale of firearms, interrupt the illegal supply of guns, deter gun possession, reduce gun carrying in public places, toughen responses to illegal gun use, reduce demand for firearms, promote responsible ownership of guns, and address community conditions that foster gun crime. In this review, we examine research on the effectiveness of selected law enforcement strategies for reducing gun crime and gun violence.OBJECTIVESThis review examines the impacts of police strategies to reduce illegal possession and carrying of firearms on gun crime. Examples include gun detection patrols in high‐crime areas, enhanced surveillance of probationers and parolees, weapon reporting hotlines, consent searches, and other similar tactics.CRITERIA FOR INCLUSION OF STUDIESStudies using randomized designs or quasi‐experimental designs involving a nonintervention condition were eligible for inclusion. Eligible studies had to include pre and post‐intervention measurements of the outcome measure(s) for an intervention area(s) or group(s) and at least one comparison area or group without the intervention. However, we also included studies involving repeated interventions with one group or area in which the intervention and comparison units consisted of samples of time with and without the intervention. Eligible studies also had to measure gun‐related crime (e.g., gun murders, shootings, gun robberies, gun assaults). The review does not include studies in which eligible interventions were implemented simultaneously with other new crime‐reduction efforts.SEARCH STRATEGYWe searched 11 national and international databases for published and unpublished literature available through the end of 2009; examined 25 reviews and compilations of research on policing, gun control, and violence reduction; and searched the websites of five prominent police and criminal justice organizations in the United States and the United Kingdom. Four studies met the inclusion criteria, reporting a total of 7 non‐randomized tests of directed patrols focused on gun carrying in three American cities (5 tests) and two Colombian cities (2 tests).DATA COLLECTION AND ANALYSISFrom each included study, we extracted data pertaining to research design, subject characteristics, intervention(s), and outcome measure(s). We present a detailed narrative assessment of each included study, followed by a qualitative and quantitative synthesis of key features and results across studies. Our synthesis does not include a statistical meta‐analysis of the results due to variability in the study designs and problems in computing a usable standardized effect size index for the studies.MAIN RESULTSSix of the seven tests (not all of which were independent) suggest that directed patrols reduced gun crime in high‐crime places at high‐risk times. The Colombian studies, which were based on before and after changes from repeated interventions measured at the city level, estimated that crackdowns on gun carrying reduced firearm homicides 10% to 15%. Estimated effects were generally larger and more variable in the American studies, which examined before and after changes in smaller target areas (beats or patrol zones) relative to changes in comparison areas. With one exception, the American studies found that gun crime declined by 29% to 71%, depending on the outcome measures and statistical techniques used. Authors' Conclusions: These studies suggest that directed patrols focused on illegal gun carrying prevent gun crimes. However, conclusions and generalizations must be qualified based on the small number of studies, variability in study design and analytic strategy across the studies, pre‐intervention differences between intervention and comparison areas, and limited data regarding factors such as implementation, crime displacement, and long‐term impact. There is also a strong need for rigorous study of other strategies to reduce illegal possession and carrying of firearms.