Introduction
”Hot spots” of crime are defined as ”small places in which the occurrence of crime is so frequent that it is highly predictable, at least over a one-year period” (Sherman 1995, 36). Hot spots are places such as street corners, malls, apartment blocks, subway stations, and public parks that generate a large number of complaints to police. Research shows that about 3% of all places generate more than half of all citizen complaints about crime and disorder to the police.
Policing these hot spots of crime is generally regarded as an effective use of scarce police resources. By targeting hot spots, research shows that the police can directly contribute to an overall reduction in crime problems in a city.
Identifying Hot Spots
Crime analysts in police departments are generally responsible for identifying hot spots of crime. Crime analysts employ sophisticated spatial analysis techniques using geographic information systems (GISs) to understand the distribution of crime and pinpoint the locations of crime hot spots. Many techniques have been used to empirically and conceptually describe the clustering of crime into hot spots, and new, innovative techniques often developed in the physical sciences are used to understand the nonrandom distributions of crime.
One recent line of inquiry in the crime and place tradition is the application of trajectory research—traditionally used to describe individual offending patterns over the life course (see Weisburd et al. 2004). The use of trajectory analysis enables researchers and crime analysts to view crime trends at places over long periods of time and to use group-based statistical techniques to uncover distinctive developmental trends and identify long-term patterns of offending in crime hot spots.
Researchers from a number of disciplines including geography, architecture, environmental planning, sociology, social psychology, political science, and criminology have helped advance the theories and methods used by crime analysts to identify hot spots of crime. The ”crime and place” perspective that informs today’s hot spots of crime research has a long history dating back to late nineteenth-century researchers in France (for example, Andre-Michel Guerry and Adolphe Quetelet) and early twentieth-century researchers in Chicago (for example, Clifford Shaw and Henry McKay). Recent research on hot spots of crime straddles a number of theoretical perspectives such as ecology of crime, environmental criminology, routine activities theory, crime pattern theory, defensible space, crime prevention through environmental design, and situational crime prevention.
Routine activities theory is particularly relevant for understanding both the reasons why crime becomes clustered in hot spots as well as for thinking through ways that the police can be effective in controlling crime problems in these places. Most recently, routine activities theory has been extended to explicitly delineate the importance of ”amenable places” (that is, hot spots) and those who discourage crimes and criminogenic places (that is, the police). John Eck refers to these people as ”place managers.” Routine activities theory crime event equation is now understood as follows: Crime occurs when there is the convergence in time of a desirable target without an effective guardian, a motivated offender without an effective handler, at a facilitating place without an attentive manager.
Places are seen as being amenable when certain place attributes influence the likelihood that a crime event will occur. For example, places located near bars or main throughways and places that have multiple access points, weak place management, or indicators of decay all correlate highly with places that become crime hot spots.
Routine activities theory as well as other crime and place theories all contribute to our understanding of why crime clusters into hot spots. Research using these theoretical perspectives consistently demonstrates that crime is not a random event but rather the result of environmental factors. These environmental (and situ-ational) factors create opportunities for crime in some places and prevent crime from occurring in others.
Sherman (1995) draws from these (and other) theories to propose six primary dimensions that help to define and distinguish one hot spot of crime from another:
1. Onset. This dimension examines the factors that cause a place to become a hot spot. Such factors that might cause the onset of a crime hot spot include change in the management of a local bar, the construction of a parking lot that has poor environmental design, some type of change in the routine activities of a neighborhood, or mere chance.
2. Recurrence. This dimension deals with the point in time when a crime analyst labels a place as a hot spot. For example, we know that when a place experiences three robberies during a one-year period, that place has a 58% chance of recurrence. Recurrence encourages us to ask whether there is a threshold of activity that would define a place as a hot spot.
3. Frequency. This dimension deals with the number of times per year crime occurs in a defined hot spot of crime.
4. Intermittency. This dimension deals with two issues. The first is the amount of time between criminal events. The second is what explains intermittency. Such factors as the criminal habits of the occupants, the economic difficulties of place owners, and changes in traffic flow that impacts the flow of targets and offenders have been considered.
5. Career length and desistence. The fifth dimension is concerned with the desistence of crime problems in a particular hot spot. Places desist from having crime problems for five reasons: death (for example, a hot spot bar is torn down), vigilante behavior (for example, omnipresence patrol by police or patrol by citizens), incapacitation (for example, civil remedies or boarding up buildings), blocking opportunities (for example, rerouting a bus route), or building insulators (for example, community cohesion and problem solving).
6. Crime types. The final dimension describes the fact that some places tend to have crime specialization because the place characteristics limit the types of crimes possible (for example, drug dealing).
Policing Hot Spots
The work of crime analysts is crucial for frontline officers to obtain a comprehensive understanding of the concentration of crime in hot spots. Results generated by crime analysts are used by operational law enforcement officers in their efforts to target police resources at hot spots involving street-level drug markets, burglary, violent crimes, traffic, gun markets, and motor vehicle theft and at other places where crime problems cluster together.
Research into hot spots of crime highlights the importance for frontline officers to use both formal as well as informal crime control efforts that specifically target hot places and seek to alter their attributes. These crime control efforts fall into two distinct categories: those that increase formal surveillance of a place (for example, increased levels of preventive patrol, or directed patrol) and those that change the environmental and situation-al characteristics of a place (for example, civil remedies or problem-oriented policing).
Evaluations of police efforts to target a variety of different types of hot spots suggest significant crime control potential for policing the hot spots of crime. Anthony Braga’s systematic review of five randomized experiments and four nonequivalent control group quasi-experiments reveals that focused police actions (for example, crackdowns, problem-oriented policing, directed patrols, aggressive patrols, raids, or civil remedies) can prevent crime and disorder in crime hot spots. His review also showed that focused police actions do not necessarily result in crime displacement, but rather crime prevention benefits were observed as a result of these focused law enforcement efforts in crime hot spots.
Generally speaking, we know that policing hot spots of crime is an effective approach for controlling street crime problems. But there are two important dimensions to understand in order to maximize the effectiveness of policing in crime hot spots. First, we need a comprehensive understanding of the policing strategies that work best in responding to crime in hot spots, and second, we need to understand whether or not different types of crime hot spots respond differently to different types of interventions. The research evidence is limited, yet instructive, on these matters.
Types of Policing Strategies Conducive to Hot Spots Policing
The types of policing strategies that are typically used to target crime hot spots include problem-oriented policing, increased presence of uniformed police patrols (directed patrols), crackdowns, court authorized raids, civil remedies, and zero tolerance policing.
Problem-oriented policing is an approach to policing in which problems are subject to in-depth examination (drawing on the specially honed skills of crime analysts and the accumulated experience of operating field personnel) in the hope that what is learned about the problem will lead police to implement new and innovative ways for dealing with it.
Crackdowns are defined as abrupt escalations in proactive enforcement activities that are intended to increase the perceived or actual threat of apprehension for certain offenses occurring in certain situations or locations. During crackdowns police operations are typically highly visible and involve uniformed and/or undercover officers.
Raids are localized search and secure-type operations that generally target residential and commercial (that is, clubs, motels, and the like) properties that are the source of numerous drug, crime, and disorder problems (that is, calls for service, arrests, or citizen complaints). Raids generally involve arrests and seizures and are typically highly visible, with the intention of acting as a deterrent to others.
Civil remedies are procedures and sanctions, specified by civil statutes and regulations, used to prevent or reduce criminal problems and incivilities. In third-party policing, the police partner with other regulators and use civil remedies to persuade or coerce nonoffending third parties to take responsibility and action to prevent or end criminal or nuisance behavior. Civil remedy approaches often target nonoffending third parties (for example, landlords or property owners) and use nuisance and drug abatement statutes to control problems.
Zero tolerance involves the strict enforcement of minor offenses.
More detailed descriptions of each of these strategies can be found elsewhere in this topic. What is important about each of these police tactics is that they have been consistently used by the police in dealing with problems in crime hot spots. Of these, problem-oriented policing and civil remedies used in third-party policing efforts show the most promise for controlling problems in crime hot spots.
Types of Crime in Hot Spots
People generally think of crime hot spots as having some level of crime specificity. Indeed, a hot spot is often thought of in terms of being a drug market hot spot or a car theft hot spot or a violent crime hot spot or that of other categories of crime. However, research suggests that some crime hot spots do experience a plethora of specific types of crime problems. For example, examining the distribution of crime problems in Minneapolis, Weisburd and his colleagues found that theft problems and domestic disturbances are two types of crime problems that showed signs of crime specificity in a hot spot. Data from the five cities (Jersey City, Kansas City, San Diego, Pittsburgh, and Hartford) involved in the Drug Markets Analysis Program funded by the National Institute of Justice reveal consistent and similar types of crime specificity for street drug market activity.
Crime-specific perspectives on crime and crime prevention, notably situational crime prevention, are useful for understanding the factors that cause specific crime problems. Analysis of the environmental causes in the crime hot spots that experience some degree of crime specialization are then used to develop highly tailored types of policing responses.
While some categories of crime tend to dominate some hot spots (such as drug-dealing places), many hot spots of crime experience a range of different types of problems, such as domestic violence, burglary, assaults, and robberies. These ”potpourri” hot spots are places that experience a clustering of different crime problems. They are likely to have environmental and situational features that operate similarly to cause a variety of problem outcomes. For example, a nightclub that has weak management and poor alcohol serving practices might be situated in an area with low levels of informal social control. This type of hot spot is likely to have a variety of problem outcomes, such as assaults, robberies, drunk and disorderly behavior, as well as domestic disputes. Policing these potpourri hot spots is usually more difficult than policing those hot spots that exhibit a high degree of crime specialization.
Conclusion
Research shows that focused police activities—such as directed patrols, raids, civil remedies, crackdowns, and problem-oriented policing—that target crime hot spots can reduce crime problems. Further, research shows that focused policing in street-level drug markets, violent crime places, and gun markets can markedly reduce crime and disorder problems in these places. Police resources for dealing with street crime problems are thus best utilized when crime prevention resources are focused at micro places with large numbers of crime events.
Recent research agrees with this ”hot spots policing” approach but adds that police need to distinguish between shortlived concentrations of crime in hot spots versus those hot spots that have long histories (see Weisburd et al. 2004). Indeed, Weisburd and his colleagues (2004) suggest that if hot spots of crime shift rapidly from place to place, it makes little sense to focus crime control resources at such locations. By contrast, the police would be most effective by identifying and targeting resources at those hot spots with long histories of crime.
