Police practices are focused primarily on people. The practices often begin with people who call the police and are focused on identifying offenders who commit crimes. They end with the arrest of those offenders and their processing through the criminal justice system. Catching criminals on a case-by-case basis and processing them through the criminal justice system remains the predominant police crime prevention strategy. My research, however, suggests that police should put places, rather than people, at the center of their practices. My point is not simply that places should be considered in policing, but that they should be a key component of the databases that police use, of the geographic organization of police activities, and of the strategic approaches that police use to combat crime and disorder.
What Is a “Place”?
Place-based policing is not simply the application of police strategies to a unit of geography. Traditional policing in this sense is place-based, since police routinely define their units of operation in terms of large areas such as precincts and beats. Place, in place-based policing, refers to a different level of geographic aggregation. Places in this context are small micro units of analysis such as buildings or addresses, block faces or street segments, or clusters of addresses. Such places where crime is concentrated are commonly called “hot spots.”
Policing Places: What Is It?
Place-based policing emphasizes the specific places where crimes are concentrated. It begins with an assumption that something about a place leads to crimes occurring there. In this sense, place-based policing is theoretically based on routine activities theory (Cohen and Felson, 1979), which identifies crime as a matter of the convergence of suitable targets (e.g., victims), an absence of capable guardians (e.g., police), and the presence of motivated or potential offenders. Of course, all these elements must occur within the context of a place or situation. Accordingly, place-based policing recognizes that something about specific places leads to the convergence of these elements.
The strategies of place-based policing can be as simple as bringing extra patrols to high crime places, as Lawrence Sherman and I did in the Minneapolis Hot Spots Policing Experiment (1995). But place-based policing can also take a much more complex approach to the amelioration of crime problems at places. In the Jersey City Drug Market Analysis Project (Weisburd and Green, 1995), for example, we used a three-step program (comprising identifying and analyzing problems, developing tailored responses, and maintaining crime control gains) to reduce problems at drug hot spots.
The Advantages of Policing Places
In the Seattle Crime Trends at Places Study (Weisburd et al., 2004), my colleagues and I showed that crime is highly concentrated in a small number of places in a city. Over a 14-year period, about 4 percent of the street segments each year were found to contain half of the crimes recorded. This concentration seems to be even greater for specific types of crime. For example, we found that 86 street segments out of 29,849 accounted for one-third of the total number of juvenile crime incidents in Seattle (Weisburd, Morris, and Groff, 2009). Comparing the concentration of crime across people as opposed to places, we found that about one-quarter as many places as people accounted for 50 percent of crime in Seattle. These data suggest that there are important opportunities for the police to identify and do something about crime by focusing on crime hot spots.
The Stability of Place-Based Targets
There is perhaps a no better-established fact in criminology than the variability and instability of offending across the life course. It is well-established that a primary factor in this variability is the fact that most offenders age out of crime often at a relatively young age. But there is also evidence of strong instability in criminal behavior for most offenders, even when short periods are observed. This may be contrasted with developmental patterns of crime at place, which suggest much stability in crime incidents over time.
In our Seattle study (Weisburd et al., 2004), we found not only that about the same number of street segments were responsible for 50 percent of the crime each year, but that the street segments that tended to evidence very low or very high activity at the beginning of the study period in 1989 were similarly ranked at the end of the period in 2002. While there are developmental trends in the data, what is most striking is the relative stability of crime, at place, over time. This also means that if the police are able to do something about crime hot spots they are likely preventing long-term chronic crime problems.
The Effectiveness of Place-Based Policing
Lawrence Sherman, Lorraine Green, and I were among the first researchers to show that hot spots policing could be effective in doing something about crime. At a time of skepticism regarding the effectiveness of police practices, we found that concentrating patrols on crime hot spots could benefit crime prevention. One long-standing objection to focusing crime prevention geographically is that it will simply shift or displace crime to other places not receiving the same level of police attention, that crime will simply “move around the corner.”
Given the common assumption of spatial displacement, my colleagues and I at the Police Foundation conducted a study in 2006 to directly test whether hot spots policing strategies did simply “move crime around the corner.” The study was singularly focused on examining to what extent immediate spatial displacement occurred as a result of hot spots policing strategies. The findings in this study reinforced a growing challenge to the displacement hypothesis. No evidence of immediate spatial displacement was found; however, strong evidence of spatial diffusion of crime control benefits was found. Places near targeted areas that did not receive special police intervention actually improved.
That study provided us with the advantage of qualitative data collection to understand why place-based policing does not simply push crime around the corner. We found that offenders did not perceive all places as having the same opportunities for crime. For example, easy access for clients was a critical criterion for drug dealers, as was relatively few residents who might call the police about prostitutes. The need for special characteristics of places to carry out criminal activity meant that crime could not simply displace to every place in a city. Indeed, the number of places evidencing such characteristics might be relatively small. In turn, spatial movement of offenders from crime sites often involved substantial effort and risk by offenders. As one drug dealer told us, “…you really can’t deal in areas you aren’t living in, it ain’t your turf. That’s how people get themselves killed.” Moreover, offenders, like nonoffenders, come to feel comfortable with their home turf and the people they encounter.
Increasing Prevention while Decreasing Incarceration
Over the past two decades, we have begun to imprison Americans at higher and higher rates. Spending on prisons has increased at more than double the rate of spending on education and health care. About 2.3 million Americans are in prisons or jails, institutions that are often dehumanizing and degrading. Policing places puts emphasis on reducing opportunities for crime at places, not on waiting for crimes to occur and then arresting offenders. 
Successful crime prevention programs at places need not lead to high numbers of arrests, especially if methods are developed that discourage offenders. In this sense, place-based policing offers an approach to crime prevention that can increase public safety while decreasing the human and financial costs of imprisonment for Americans. If place-based policing were to become the central focus of police crime prevention, rather than the arrest and apprehension of offenders, we would likely see at the same time a reduction of prison populations and an increase in the crime prevention effectiveness of the police.
What Must Be Done?
For place-based policing to succeed, police must change their unit of analysis for understanding and doing something about crime. My research suggests that it is time for police to shift from person-based policing to place-based policing. While such a shift is largely an evolution in trends that have begun over the past few decades, it will nonetheless demand radical changes in data collection in policing, the organization of police activities, and particularly the overall worldview of the police. It remains true today that police officers see the key work of policing as catching criminals. It is time to change that worldview, so that police understand that the key to crime prevention is in ameliorating crime at place.
Bibliography
Cohen, L. E., and M. Felson (1979). Social Change and Crime Rate Trends: A Routine Activity Approach. American Sociological Review 44, 588-605.
Sherman, L., and D. Weisburd (1995). General Deterrent Effects of Police Patrol in Crime “Hot Spots”: A Randomized Study. Justice Quarterly 12(4), 625-648.
Weisburd, D., and L. Green (1995). Policing Drug Hot Spots: The Jersey City DMA Experiment. Justice Quarterly 12(4), 711-735.
Weisburd, D., S. Bushway, C. Lum, et al. (2004). Crime Trajectories at Places: A Longitudinal Study of Street Segments in the City of Seattle. Criminology 42(2), 283-322.
Weisburd, D., L. Wyckoff, J. Ready, et al. (2006) Does Crime Just Move around the Corner?: A Controlled Study of Spatial Displacement and Diffusion of Crime Control Benefits. Criminology 44(3), 549-591.
Weisburd, D., N. Morris, and E. Groff (2009). Hot Spots of Juvenile Crime: A Longitudinal Study of Arrest Incidents at Street Segments in Seattle, Washington. Journal of Quantitative Criminology 25; 443-467.
May 21, 2011