Focused Deterrence Strategies
- Anthony BragaAnthony BragaDepartment of Criminology and Criminal Justice, Northeastern University
Focused deterrence strategies are increasingly being implemented in the United States to reduce serious violent crime committed by gangs and other criminally-active groups, recurring offending by highly-active individual offenders, and crime and disorder problems generated by overt street-level drug markets. These strategies are framed by an action research model that is common to both problem-oriented policing and public health interventions to reduce violence. Briefly, focused deterrence strategies seek to change offender behavior by understanding underlying crime-producing dynamics and conditions that sustain recurring crime problems and by implementing an appropriately focused blended strategy of law enforcement, community mobilization, and social service actions. Direct communications of increased enforcement risks and the availability of social service assistance to target groups and individuals is a defining characteristic of “pulling levers” strategies.
The focused deterrence approach was first pioneered in Boston, Massachusetts and eventually tested in other jurisdictions. The available empirical evidence suggests these strategies generate noteworthy violence reduction impacts and should be part of a broader portfolio of crime reduction strategies available to policy makers and practitioners. While focused deterrence strategies attempt to prevent crime by changing offender perceptions of sanction risk, complementary crime prevention efforts seem to support the crime control efficacy of these programs. These strategies also seek to change offender behavior by mobilizing community action, enhancing procedural justice, and improving police legitimacy. Focused deterrence strategies hold great promise in reducing serious violence while improving strained relationships between minority neighborhoods and the police departments that serve them.
A New Framework for Addressing Crime Problems
A recent innovation in community violence prevention that capitalizes on the growing evidence of the effectiveness of police deterrence strategies is the “focused deterrence” framework, sometimes referred to as “pulling-levers policing” (Kennedy, 1997, 2008). Focused deterrence strategies honor core deterrence ideas, such as increasing risks faced by offenders, while finding new and creative ways of deploying traditional and non-traditional law enforcement tools to do so, such as directly communicating incentives and disincentives to targeted offenders (Kennedy, 1997, 2008). The approach has been applied to control violent behavior by gangs and other criminally active groups (Braga, Kennedy, Waring, & Piehl, 2001; McGarrell, Chermak, Wilson, & Corsaro, 2006; Papachristos & Kirk, 2015), violence and disorder generated by overt drug markets (Corsaro, Hunt, Hipple, & McGarrell, 2012; Kennedy & Wong, 2009), and serious violent behavior by individual chronic offenders (Papachristos, Meares, & Fagan, 2007). The available evaluation research suggests that focused deterrence strategies, when implemented correctly, generate large reductions in targeted crime problems (Braga & Weisburd, 2012). Anecdotal evidence suggests that these approaches can help improve police-community relationships in disadvantaged minority communities and reduce our reliance arrests and mass incarceration as means to address violent crime (Kennedy, 2011).
While the available evaluation evidence is very supportive of deterrence principles, it seems very likely that other complementary crime control mechanisms are at work in the focused deterrence strategies that need to be highlighted and better understood (Braga, 2012). In the focused deterrence approach, the emphasis is not only on increasing offender perceptions of risk, it is also on decreasing opportunity structures for violence, deflecting offenders away from crime, increasing the collective efficacy of communities, and increasing the legitimacy of law enforcement actions. Indeed, it seems likely that the observed crime control gains come precisely from the multi-faceted ways in which this program influences criminals.
Given the available empirical evidence and promising claims, it is not surprising that focused deterrence strategies have become a very popular way to address inner-city violence. Pioneered in Boston as a problem-oriented policing project to halt serious gang violence during the 1990s (Braga et al., 2001; Kennedy, Piehl, & Braga, 1996), 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). The National Network for Safe Communities, an organization that promotes the use of focused deterrence strategies, reports that some 73 cities across 27 U.S. states have implemented or are in the process of implementing the strategy.1 Experiences in Glasgow, Scotland suggest that the approach may be beneficial in addressing serious youth violence problems in other western countries (Deuchar, 2013). Police executives and other public officials in eastern and South American countries, such as Turkey and Brazil, have also explored the possibility of implementing focused deterrence strategies to control gang and group-related violence in their cities (National Network for Safe Communities, 2013).
This article begins by tracing the development of focused deterrence strategies in Boston and then describes experiences in other cities. Explicit links are then made between focused deterrence strategies and public health approaches to violence prevention. Theoretical perspectives supporting the implementation of focused deterrence strategies are subsequently reviewed. The available program evaluation showing the crime prevention efficacy of focused deterrence strategies is then presented. The concluding section of the article describes the promise of these approaches in improving the legitimacy of the police by promoting fair and effective law enforcement.
Focused Deterrence Strategies
Focused deterrence strategies attempt to influence the criminal behavior of individuals through the strategic application of enforcement and social service resources to facilitate desirable behaviors. Focused deterrence strategies are often framed as problem-oriented exercises where specific recurring crime problems are analyzed and responses are highly customized to local conditions and operational capacities. As described by Kennedy (2006, pp. 156–157), focused deterrence operations have tended to follow this basic framework:
Selection of a particular crime problem, such as serious gun violence.
Pulling together an interagency enforcement group, typically including police, probation, parole, state and federal prosecutors, and sometimes, federal enforcement agencies.
Conducting research, usually relying heavily on the field experience of front-line police officers, to identify key offenders—and frequently groups of offenders, such as street gangs, drug crews, and the like—and the context of their behavior.
Framing a special enforcement operation directed at those offenders and groups of offenders, and designed to substantially influence that context, for example by using any and all legal tools (or levers) to sanction groups such as crack crews whose members commit serious violence.
Matching those enforcement operations with parallel efforts to direct services and the moral voices of affected communities to those same offenders and groups.
Communicating directly and repeatedly with offenders and groups to let them know that they are under particular scrutiny, what acts (such as shootings) will get special attention, when that has in fact happened to particular offenders and groups, and what they can do to avoid enforcement action. One form of this communication is the “forum,” “notification,” or “call-in,” in which offenders are invited or directed (usually because they are on probation or parole) to attend face-to-face meetings with law enforcement officials, service providers, and community figures.
The Boston Gun Project and Operation Ceasefire in the 1990s
The Boston Gun Project was a problem-oriented policing enterprise expressly aimed at taking on a serious, large-scale crime problem—homicide victimization among young people in Boston. Like many large cities in the United States, Boston experienced a large sudden increase in youth homicide between the late 1980s and early 1990s. The Project began in early 1995 and implemented what is now known as the “Operation Ceasefire” intervention, which started in the late spring of 1996 (Kennedy et al., 1996). Led by the Boston Police Department’s (BPD) Youth Violence Strike Force (YVSF, informally known as the “gang unit”), a working group of law enforcement personnel, youth workers, and Harvard University researchers diagnosed the youth violence problem in Boston as one of patterned, largely vendetta-like (“beef”) hostility amongst a small population of chronic offenders, and particularly among those involved in loose, informal, mostly neighborhood-based gangs (Kennedy, Braga, & Piehl, 1997). These gangs represented less than 1% of the city’s youth between the ages of 14 and 24, but were responsible for more than 60% of youth homicide in Boston.
The focused deterrence strategy behind Operation Ceasefire was designed to prevent violence by reaching out directly to gangs, saying explicitly that violence would no longer be tolerated, and backing up that message by “pulling every lever” legally available when violence occurred (Kennedy, 1997, 2011). The chronic involvement of gang members in a wide variety of offenses made them—and their groups—vulnerable to a coordinated criminal justice response. The YVSF and their criminal justice partners could disrupt street drug activity, focus police attention on low-level street crimes such as trespassing and public drinking, serve outstanding warrants, cultivate confidential informants for medium- and long-term investigations of gang activities, deliver strict probation and parole enforcement, seize drug proceeds and other assets, ensure stiffer plea bargains and sterner prosecutorial attention, request stronger bail terms (and enforce them), and bring potentially severe federal investigative and prosecutorial attention to gang-related drug and gun activity. Rather than simply dealing with individual offending, groups were held accountable for outbreaks of serious gun violence.
Simultaneously, youth workers, probation and parole officers, and later churches and other community groups offered gang members services and other kinds of help. These partners also delivered an explicit message that violence was unacceptable to the community and that “street” justifications for violence were mistaken. The Ceasefire Working Group delivered this message in formal meetings with gang members (known as “forums” or “call-ins”), through individual police and probation contacts with gang members, through meetings with inmates at secure juvenile facilities in the city, and through gang outreach workers. The deterrence message was not a deal with gang members to stop violence. Rather, it was a promise to gang members that violent behavior would evoke an immediate and intense response. If gangs committed other crimes but refrained from violence, the normal workings of police, prosecutors, and the rest of the criminal justice system dealt with these matters. But if gang members persisted in their violent behaviors, the Working Group concentrated its enforcement actions on their gangs.
The idea of the Ceasefire “crackdowns” specifically, but the focused deterrence model more generally, was not to eliminate gangs or stop every aspect of gang activity, but rather to control and deter serious violence among specified groups (Kennedy, 1997). To do this, the Working Group explained its actions against targeted gangs to other gangs, as in “this gang did violence, we responded with the following actions, and here is how to prevent anything similar from happening to you.” The ongoing Working Group process regularly watched the city for outbreaks of gang violence and framed any necessary responses in accord with the Ceasefire strategy. As the strategy unfolded, the Working Group continued communication with gangs and gang members to convey its determination to stop violence, to explain its actions to the target population, and to maximize both voluntary compliance and the strategy’s deterrent power.
A large reduction in the yearly number of Boston youth homicides followed immediately after Operation Ceasefire was implemented in mid-1996. A U.S. Department of Justice (DOJ)-sponsored quasi-experimental evaluation of Operation Ceasefire revealed that the intervention was associated with a 63% decrease in the monthly number of Boston youth homicides, a 32% decrease in the monthly number of shots-fired calls, a 25% decrease in the monthly number of gun assaults, and, in one high-risk police district given special attention in the evaluation, a 44% decrease in the monthly number of youth gun assault incidents (Braga et al., 2001). The evaluation also suggested that Boston’s significant youth homicide reduction associated with Operation Ceasefire was distinct when compared to youth homicide trends in most major U.S. and New England cities (Braga et al., 2001). In a companion paper to the main impact evaluation, Piehl, Cooper, Braga, and Kennedy (2003) developed an econometric model that evaluated all possible monthly break points in the time series to identify the maximal monthly break point associated with a significant structural change in the trajectory of the time series. Controlling for trends and seasonal variations, the timing of the “optimal break” in the monthly counts of youth homicides time series was in the summer months after Ceasefire was implemented in 1996.
Given the high profile of the Boston experience, the Ceasefire evaluation has been reviewed by a number of researchers and the relationship between the implementation of Ceasefire and the trajectory of youth homicide in Boston during the 1990s has been closely scrutinized. The evaluation methodology and results were greeted both with a healthy dose of skepticism (Fagan, 2002; Rosenfeld, Fornango, & Baumer, 2005) and some support (Cook & Ludwig, 2006; Morgan & Winship, 2007). The National Academies’ Committee on Improving Information and Data on Firearms (Wellford, Pepper, & Petrie, 2005) concluded that the Ceasefire evaluation was compelling in associating the intervention with the subsequent decline in youth homicide. However, the committee also suggested that many complex factors affect youth homicide trends, and it was difficult to specify the exact relationship between the Ceasefire intervention and subsequent changes in youth offending behaviors. The committee further observed that the Ceasefire evaluation examined aggregate citywide data and did not provide any empirical evidence that treated gangs modified their violent behaviors after being exposed to the intervention.
Operation Ceasefire in the 2000s
Despite the national acclaim, the BPD discontinued the Ceasefire strategy as its primary response to outbreaks of gang violence in January 2000 (see Braga & Winship, 2006). Yearly counts of gang homicides, unfortunately, increased linearly after Ceasefire was halted in Boston (Braga, Hureau, & Winship, 2008). In 1999, the last full year of Ceasefire intervention, there were only 5 gang-motivated homicides in Boston. By 2006, this number had increased more than seven-fold to 37 gang-motivated homicides in Boston. During this time period, the BPD experimented with alternative approaches to violence prevention by adapting certain Ceasefire tactics to a broader range of problems such as investigating unsolved shootings, facilitating the re-entry of incarcerated violent offenders back into high-risk Boston neighborhoods, and addressing criminogenic families in hot spot areas (Braga & Winship, 2006). Unfortunately, the slate of new approaches seemed to diffuse the ability of the City of Boston to deal with gang violence, as no one group was focused exclusively on addressing ongoing conflicts among street gangs (Braga et al., 2008).
At the beginning of December 2006, newly appointed BPD Commissioner Edward F. Davis announced that Operation Ceasefire would once again be the BPD’s main response to outbreaks of serious gang violence (Braga, Hureau, & Papachristos, 2014). The YVSF reinstated the Ceasefire approach as a citywide, interagency effort to disrupt ongoing cycles of gang violence, and regular Working Group meetings soon commenced. The Lucerne Street Doggz was the first group selected for Ceasefire intervention because it was the city’s most violent gang of that time period. The Doggz were a loosely organized gang based in the disadvantaged Lucerne Street area of the Mattapan section of Boston. In 2006, the Lucerne gang had roughly 50 members and was involved in violent disputes with eight rival gangs—Big Head Boys, Morse Street, Norfolk, Greenwood, Heath Street, Orchard Park, H-Block, and Winston Road. In fact, problem analysis research revealed that Lucerne was involved in 37 fatal and non-fatal shootings in 2006, representing nearly 10% of all shootings in Boston that year.
The YVSF partnered with the same criminal justice, social service, and community-based partners from the strategy’s first incarnation on a call-in to deliver the Ceasefire anti-violence message to the Lucerne Street Doggz. However, after the call-in, Lucerne continued its torrid involvement in shootings and, by the end of May 2007, was the suspect group in another 21 gang-involved shootings and the victim group in another 6 gang-involved shootings. Consistent with the overall focused deterrence strategy, it was critical to establish the credibility of the Ceasefire anti-violence message on the streets of Boston again. Since Lucerne had been subjected to a call-in and continued on its violent path, the Ceasefire working group needed to make good on the promise that a strong law enforcement response would soon follow. On May 24, 2007, 25 Lucerne Street gang members were taken into custody and charged with federal and state drug and firearms offenses (Braga et al., 2014). As Figure 1 reveals, the impact of the Ceasefire intervention on their gun violence behavior was noteworthy. In 2006 and 2007, Lucerne gang averaged 33.5 total shootings per year. Their yearly average plummeted by 87.2% to 4.3 per year between 2008 and 2010.
Between January 2007 and December 2010, 19 Boston gangs were subjected to the Ceasefire focused deterrence strategy. Braga et al. (2014) conducted a rigorous quasi-experimental evaluation of the reconstituted Boston Ceasefire program that used statistical matching techniques to develop balanced treatment gangs and comparison gangs. Growth-curve regression models were then used to estimate the impact of Ceasefire on gun violence trends for the matched treatment gangs relative to matched comparisons gangs during the 2006 through 2010 study time period. The evaluation reported that total shootings involving directly treated Ceasefire gangs were reduced by a statistically significant 31% relative to total shootings involving comparison gangs. Using similar evaluation methods, Braga, Apel, and Welsh (2013) found that the Ceasefire strategy also created spillover deterrent effects onto other gangs that were socially connected to targeted gangs through rivalries and alliances. Total shootings involving these “vicariously treated” gangs also decreased by a statistically significant 24% relative to total shootings by matched comparison gangs.
Gang and Group Violence Reduction Efforts in Other Cities
There have been subsequent replications of the Boston “pulling levers” focused deterrence strategy centered on preventing serious violence by gangs and criminally-active groups, such as U.S. Department of Justice-sponsored research and development exercises in Los Angeles, California (Tita et al., 2004), and Indianapolis, Indiana (McGarrell et al., 2006). Consistent with the problem-oriented policing approach, these cities have tailored the approach to fit their violence problems and operating environments. Operation Ceasefire in the Hollenbeck area of Los Angeles was framed to “increase the cost of violent behavior to gang members while increasing the benefits of nonviolent behavior” (Tita, Riley, Ridgeway, Grammich, Abrahamse, & Greenwood, 2004, p. 10). In the wake of the federal prosecution of a very violent street gang, the Indianapolis Violence Reduction Partnership used face-to-face “lever-pulling” meetings with groups of high-risk probationers and parolees to communicate a deterrence message that gun violence would provoke an immediate and intense law enforcement response. At the meetings, targeted groups of probationers and parolees were also urged to take advantage of a range of social services and opportunities, including employment, mentoring, housing, substance abuse treatment, and vocational training (McGarrell et al., 2006, p. 319).
The approaches used to get the attention of violent gang members can be quite creative, as enforcement interventions are artfully tailored to criminal offending patterns exhibited by specific groups. Supported by funds from the U.S. Department of Justice-sponsored Project Safe Neighborhoods initiative, an interagency task force implemented a pulling levers focused deterrence strategy to prevent gun violence among Hispanic and Asian gangs in Lowell, Massachusetts in 2002 (Braga, McDevitt, & Pierce, 2006). While the Lowell authorities felt very confident about their ability to prevent violence among Hispanic gangs by pursuing a general focused deterrence strategy, they felt much less confident about their ability to prevent Asian gang violence by applying the same set of criminal justice levers to Asian gang members. As Malcolm Klein (1995) suggests, Asian gangs have some key differences from typical black, Hispanic, and white street gangs. They are more organized, have identifiable leaders, and are far more secretive. They also tend to be far less territorial and less openly visible. Therefore, their street presence is low compared to other ethnic gangs. Relationships between law enforcement agencies and the Asian community are often characterized by mistrust and a lack of communication (Chin, 1996). As such, it is often difficult for the police to develop information on the participants in violent acts to hold offenders accountable for their actions.
During the intervention time period, the Lowell Police Department (LPD) had little reliable intelligence about Asian gangs in the city (Braga et al., 2006). The LPD had attempted to develop informants in the past but most of these efforts had been unsuccessful. With the increased focus on Asian gang violence, the LPD increased its efforts to develop intelligence about the structure of the city’s Asian gangs, particularly the relationship between Asian gang violence and ongoing gambling that was being run by local Asian businesses. Asian street gangs are sometimes connected to adult criminal organizations and assist older criminals in extortion activities and protecting illegal gambling enterprises (Chin, 1996). In many East Asian cultures, rituals and protocols guiding social interactions are well defined and reinforced through a variety of highly developed feelings of obligation, many of which are hierarchical in nature (Zhang, 2002). This facilitates some control over the behavior of younger Asian gang members by elders in the gang.
In Lowell, Cambodian and Laotian gangs were comprised of youth whose street activities were influenced by “elders” of the gang (Braga et al., 2006). Elders were generally long-time gang members in their 30s and 40s, who no longer engaged in illegal activities on the street or participated in street-level violence with rival youth. Rather, these older gang members were heavily involved in running illegal gambling dens and informal casinos that were operated out of cafes, video stores, and warehouses located in the poor Asian neighborhoods of Lowell. The elders used young street gang members to protect their business interests and to collect any unpaid gambling debts. Illegal gaming was a very lucrative business that was much more important to the elders than any ongoing beefs the youth in their gang had with other youth (Braga et al., 2006). In contrast to acquiring information on individuals responsible for gun crimes in Asian communities, it was much easier to detect the presence of gambling operations through surveillance or a simple visit to the suspected business establishment.
The importance of illegal gaming to influential members of Asian street gangs provided a potentially potent lever to law enforcement in preventing violence. The authorities in Lowell believed that they could systematically prevent street violence among gangs by targeting the gambling interests of older members. When a street gang was violent, the LPD targeted the gambling businesses run by the older members of the gang. The enforcement activities ranged from serving a search warrant on the business that housed the illegal enterprise and making arrests to simply placing a patrol car in front of the suspected gambling location to deter gamblers from entering. The LPD coupled these tactics with the delivery of a clear message, “when the gang kids associated with you act violently, we will shut down your gambling business. When violence erupts, no one makes money” (Braga et al., 2006, p. 40). Between October 2002 and June 2003, the height of the focused attention on Asian gangs, the LPD conducted some 30 search warrants on illegal gambling dens that resulted in more than 100 gambling-related arrests (Braga et al., 2006).
An impact evaluation found that the Lowell focused deterrence strategy was associated with a 43% decrease in the monthly number of gun homicide and gun aggravated assault incidents (Braga, Pierce, McDevitt, Bond, & Cronin, 2008). A comparative analysis of gun homicide and gun aggravated assault trends in Lowell relative to other major Massachusetts cities also supports a unique program effect associated with the focused deterrence intervention.
Applying Focused Deterrence to Individual Offenders
A variation of the Boston model was applied in Chicago, Illinois, as part of the U.S. Department of Justice–sponsored Project Safe Neighborhoods (PSN) initiative. Gun- and gang-involved parolees returning to selected highly dangerous Chicago neighborhoods went through “offender notification forums,” where they were informed of their vulnerability as felons to federal firearms laws with stiff mandatory minimum sentences, were offered social services, and were addressed by community members and ex-offenders (Papachristos et al., 2007). The forums were designed to stress to participants the consequences should they choose to pick up a gun and the choices they have to make to ensure that they do not reoffend. In addition to encouraging individual deterrence, the Chicago forums were designed explicitly to promote positive normative changes in participant behavior through an engaging communications process that participants would be likely to perceive as procedurally just, rather than simply threatening. Additionally, the Chicago program focused on matching participants to services as soon as feasible, avoiding long waits for services that had been observed in other jurisdictions.
The PSN treatment was focused on newly released prisoners with a very high risk of being a victim or offender of gun violence in two treatment police districts. A quasi-experimental evaluation compared serious violent crime trends in targeted policing districts to serious violent crime trends in matched policing districts (Papachristos et al., 2007). The evaluation revealed that the PSN program was associated with a 37% reduction in homicide in treatment districts relative to comparison districts. A supplemental quasi-experimental analysis examined whether the treatment reduced violent recidivism of program participants (Wallace, Papachristos, Meares, & Fagan, 2016). These analyses found that those who attended a PSN forum were 30% less likely to be rearrested relative to a comparison group of similar, recently released individuals from the same neighborhood.
Applying Focused Deterrence to Overt Drug Markets
There is less experience in applying the focused deterrence approach to other crime and disorder problems. In High Point, North Carolina, a focused deterrence strategy was aimed at eliminating public forms of drug dealing such as street markets and crack houses by warning dealers, buyers, and their families that enforcement is imminent (Kennedy & Wong, 2009). With individual “overt” drug markets as the unit of work, the project employed a joint police-community partnership to identify individual offenders; notify them of the consequences of continued dealing; provide supportive services through a community-based resource coordinator; and convey an uncompromising community norm against drug dealing. This application of focused deterrence is generally referred to as the “Drug Market Intervention” (DMI) strategy.
The DMI seeks to shut down overt drug markets entirely (Kennedy & Wong, 2009). Enforcement powers are used strategically and sparingly, employing arrest and prosecution only against violent offenders and, when nonviolent offenders have resisted all efforts to get them to desist, to provide them with help. Through the use of “banked” cases (i.e., drug selling cases that are available against specific offenders but not initially pursued), the strategy makes the promise of law enforcement sanctions against dealers extremely direct and credible, so that dealers are in no doubt concerning the consequences of offending and have good reason to change their behavior. The strategy also brings powerful informal social control to bear on dealers from immediate family and community figures. The strategy organizes and focuses services, help, and support on dealers so that those who are willing have what they need to change their lives. Each operation also includes a maintenance strategy.
In a simple descriptive assessment of the High Point DMI, Kennedy and Wong (2009) reported the target drug market disappeared in the treatment area (as measured by direct observation and mechanisms such as attempted drug buys by undercover officers and informants) and that violent crime decreased 39% and drug crime decreased by 30%. In a more rigorous quasi-experimental evaluation, Corsaro et al. (2012) analyzed longitudinal data to estimate program effects on violent crime trends in treated High Point neighborhoods relative to violent crime trends in matched comparison High Point neighborhoods. This evaluation reported more modest 12%–18% reductions in violent crime in the treated areas relative to control areas (Corsaro et al., 2012). More recently, Saunders, Lundberg, Braga, Ridgeway, and Miles (2015) applied a synthetic control group quasi-experimental design to evaluate the High Point DMI program and reported a 21% reduction in general crime rates in treated areas, with little evidence of spatial crime displacement.
Links to Public Health Perspectives on Violence Prevention
In a recent article, Braga and Weisburd (2015) argued that focused deterrence strategies fit well with public health perspectives on violence prevention. In general, a public health approach involves three elements: (a) a focus on prevention, (b) a focus on scientific methodology to identify risk and patterns, and (c) multidisciplinary collaboration to address the issue (Institute of Medicine, 2008). Ecological frameworks to analyze gun violence problems, a tool used in both criminology and public health, guide the analysis of potential interventions to design an appropriate strategy to prevent or reduce firearm violence. Multi-disciplinary collaborations are necessary to address complex individual, situational, and neighborhood risk factors that comprise persistent urban gun violence problems. Complementary to these public health perspectives, academic-practitioner research partnerships and interagency working groups are two core components of focused deterrence strategies that deserve further consideration here.
Academic-Practitioner Research Partnerships
The activities of the research partners in focused deterrence initiatives depart from traditional research and evaluation roles usually played by academics. The integrated researcher/practitioner partnerships in the working group setting more closely resemble policy analysis exercises that blend research, policy design, action, and evaluation (Goldstein, 1990; Kennedy & Moore, 1995). Researchers have been important assets in all of the projects described, providing what is essentially “real time” social science aimed at refining the working group’s understanding of the problem, creating information products for both strategic and tactical use, testing—often in a very elementary, but important, fashion—candidate intervention ideas, and maintaining a focus on clear outcomes and the evaluation of performance. In addition, researchers played important roles in organizing the projects (Braga, Kennedy, & Tita, 2002).
Academic research partners in focused deterrence strategies conduct epidemiological inquiries into the nature of local gun violence problems so interventions can be appropriately customized to the underlying conditions and situations that cause violent gun injuries to recur. Indeed, public health perspectives point to the importance of identifying and understanding problems as they aggregate across individuals or groups (Moore, Prothrow-Stith, Guyer, & Spivak, 1994). Frequently, this involves analyses of the geographic and network-based concentration of gun violence that are not unlike many public health analyses of the localized transmission of disease. For example, Braga, Papachristos, and Hureau’s (2010) analysis of the persistent geographic concentration of gun violence in small “hot spot” areas has some parallels with the Kerani, Handcock, Handsfield, and Holmes (2005) study of the spatial concentration of four different sexually transmitted diseases. Sophisticated network analyses of street gangs and high-rate youth offenders suggest that most of the risk of gun violence concentrates in small networks of identifiable individuals, and that the risk of homicide and non-fatal gunshot injury is associated not only with individual-level risk factors, but also the contours of one’s social network (Papachristos, 2009; Papachristos, Braga, & Hureau, 2012). The identification and analysis of gun violence problems with respect to area concentration and underlying networks bears a close correspondence to the idea of the “social epidemiology” of HIV/AIDS, as described by Poundstone, Strathdee, and Celentano (2004).
The underlying etiology of hot spots and their analogs (e.g., repeat offenders, victims) generally points toward the need for a concerted, targeted prevention strategy (Braga & Weisburd, 2010, 2012; Weisburd, Groff, & Yang, 2014). The action-oriented approach found in many focused deterrence programs is similar to the public health posture towards understanding and intervening in youth violence problems (Mercy, Rosenberg, Powell, Broome, & Roper, 1993). The initial stage of the process entails identifying and tracking the problem (e.g., elevated level of violent crime in a neighborhood) by means of some surveillance system. This is followed by an effort to understand the risk factors that contribute to the problem (e.g., actions between rival gangs) and to develop an approach to ameliorate the problem and evaluate it. Finally, the gun violence prevention strategy may be introduced to other areas that face similar problems.
Convening an Interagency Working Group with a Locus of Responsibility for Action
Missing from the account of focused deterrence strategies reported in most law enforcement circles is the larger story of an evolving collaboration that spanned the boundaries that divide criminal justice agencies from one another, criminal justice agencies from human service agencies, and criminal justice agencies from the community. As suggested by the Institute of Medicine and National Research Council (2013), such collaborations are necessary to legitimize, fund, equip, and operate complex strategies that are most likely to succeed in both controlling and preventing youth gun violence. In essence, the cities that implemented focused deterrence strategies leveraged resources through the creation of a very powerful “network of capacity” to prevent youth gun violence (Moore, 2002). These networks were well positioned to launch an effective response to recurring gun violence problems because criminal justice agencies, community groups, and social service agencies coordinated and combined their efforts in ways that could magnify their separate effects. Successfully implemented focused deterrence strategies capitalized on these existing relationships by focusing these networks on the problem of gang-related gun violence.
Criminal justice agencies, unfortunately, work largely independent of each other, often at cross-purposes, often without coordination, and often in an atmosphere of distrust and dislike (Braga et al., 2002). This is often true of different elements operating within agencies. The capacity to deliver a meaningful violence prevention intervention within cities was created by convening an interagency working group of line-level personnel with decision-making power that could assemble a wide range of incentives and disincentives. It was also important to place a locus of responsibility for reducing gun violence on the group. Prior to the creation of the interagency working groups, no one organization in these cities was responsible for developing and implementing an overall strategy for reducing gun violence.
Criminal justice agency partnerships provided a varied menu of enforcement options that could be tailored to particular gangs. Without these strategic partnerships, the available “levers” that could be pulled by the working group would have been limited. Social service and opportunity provision agencies were integrated into focused deterrence interventions to provide a much-needed “carrot” to balance the law enforcement “stick.” The inclusion of prevention and intervention programs, such as gang outreach workers (also known as “streetworkers”) in focused deterrence interventions was vitally important in securing community support and involvement in the program. Braga and Winship (2006) suggest that the legitimacy conferred upon the Boston Ceasefire initiative by key community members such as black clergy members was an equally important condition that facilitated the successful implementation of this innovative program. Public health research also suggests that streetworkers may help to reduce violent gun injuries by mediating ongoing conflicts among gangs (Webster, Whitehill, Vernick, & Parker, 2012).
Theoretical Perspectives Supporting Focused Deterrence
Deterrence theory suggests that crime can be prevented when the costs of committing the crime are perceived by the offender to outweigh the benefits (Gibbs, 1975; Zimring & Hawkins, 1973). Most discussions of the deterrence mechanism distinguish between “general” and “special” deterrence (Cook, 1980). General deterrence is the idea that the general population is dissuaded from committing crime when it sees that punishment necessarily follows the commission of a crime. Special deterrence involves punishment administered to criminals with the intent to discourage them from committing crimes in the future. Much of the literature evaluating deterrence focuses on the effect of changing certainty, swiftness, and severity of punishment associated with certain acts on the prevalence of those crimes (Apel & Nagin, 2011; Nagin, 1998; Paternoster, 1987).
In addition to any increases in certainty, swiftness, and severity of sanctions associated with gun violence, focused deterrence strategies seek to prevent violent gun injuries through the advertising of the law enforcement strategy, and the personalized nature of its application. Gang-involved youth must understand the new anti-violence regimes being imposed. The effective operation of general deterrence is dependent on the communication of punishment threats to relevant audiences. As Zimring and Hawkins (1973, p. 142) observe, “the deterrence threat may best be viewed as a form of advertising.” One noteworthy example of this principle is an evaluation of Massachusetts’ 1975 Bartley-Fox amendment, which introduced a mandatory minimum one-year prison sentence for the illegal carrying of firearms. The high degree of publicity attendant upon the amendment’s passage, some of which was inaccurate, was found to increase citizen compliance with existing legal stipulations surrounding firearm acquisition and possession, some of which were not in fact addressed by the amendment (Beha, 1977). Zimring and Hawkins (1973, p. 149) further observe that, “if the first task of the threatening agency is the communication of information, its second task is persuasion.”
The available research suggests that deterrent effects are ultimately determined by offender perceptions of sanction risk and certainty (Nagin, 1998). Durlauf and Nagin (2011, p. 40) observe that, “strategies that result in large and visible shifts in apprehension risk are most likely to have deterrent effects that are large enough not only to reduce crime but also apprehensions,” and they identified focused deterrence strategies as having these characteristics. As described, focused deterrence strategies are targeted on very specific behaviors by a relatively small number of chronic offenders who are highly vulnerable to criminal justice sanctions. The approach directly confronts gang youth and informs them that continued gun offending will not be tolerated and how the system will respond to violations of these new behavior standards. Face-to-face meetings with gang youth are an important first step in altering their perceptions about sanction risk (Horney & Marshall, 1992; Nagin, 1998). As McGarrell et al. (2006) suggest, direct communications and affirmative follow-up responses are the types of new information that may cause gang members to reassess the risks of committing violent gun injuries.
Other Theoretical Perspectives
Many scholars suggest that there are other complementary violence reduction mechanisms at work in the focused deterrence strategies described here that need to be highlighted and better understood (Braga, 2012). In Durlauf and Nagin’s (2011) article, the focus is on the possibilities for increasing perceived risk and deterrence by increasing police presence. However, in the focused deterrence approach, the emphasis is not only on increasing the risk of offending, it is also on decreasing opportunity structures for violence, deflecting offenders away from violence, increasing the collective efficacy of communities, and increasing the legitimacy of police actions. Indeed, program designers and implementers sought to generate large violent gun injury impacts from the multi-faceted ways in which this strategy influences gang-involved youth (Kennedy, 1997, 2011).
Discouragement emphasizes reducing the opportunities for crime and increasing alternative opportunity structures for offenders (Clarke, 1997). In this context, situational crime prevention techniques are often implemented as part of the core “pulling levers” work in focused deterrence strategies (Braga & Kennedy, 2012). Extending guardianship, assisting natural surveillance, strengthening formal surveillance, reducing the anonymity of offenders, and utilizing place managers can greatly enhance the range and the quality of the varying enforcement and regulatory levers that can be pulled on offending groups and key actors in criminal networks. The focused deterrence approach also seeks to redirect offenders away from violent crime through the provision of social services and opportunities. Gang members are offered job training, employment, substance abuse treatment, housing assistance, and a variety of other services and opportunities.
Sampson, Raudenbush, and Earls (1997) emphasize the capacity of a community to realize common values and regulate behavior within it through cohesive relationships and mutual trust among residents. They argue that the key factor determining whether crime will flourish is a sense of the “collective efficacy” of a community. A community with strong collective efficacy is characterized by high capacities for collective action for the public good. Pulling levers focused deterrence strategies enhances collective efficacy in communities by emphasizing the importance of engaging and enlisting community members in the strategies developed. The High Point DMI strategy, for example, drew upon collective efficacy principles by engaging family, friends, and other “influential” community members in addressing the criminal behaviors of local drug dealers (Kennedy & Wong, 2009).
Community-based action in focused deterrence strategies helps to remove the justifications used by offenders to explain away their responsibility for the targeted behavior. In call-ins and on the street, community members effectively invalidate the excuses for criminal behavior by challenging the norms and narratives that point to racism, poverty, injustice, and the like. In Boston, for example, black clergy challenged gang members who attempted to use these excuses by countering that poverty, racism, and injustice were not linked to their decisions to fire shots in their neighborhoods and kill other young people who have experienced the same societal ills and life difficulties. Community members also work with law enforcement and social service agencies to set basic rules for group-involved offenders such as “don’t shoot guns” and, hopefully, to alert the conscience of these offenders by appealing to moral values inherent in taking the life of another, causing harm to their neighborhood, or the pain that would be experienced by their mothers if they were killed or sent to prison for a long time in a very far away location.
Finally, the focused deterrence approach takes advantage of recent theorizing regarding procedural justice and legitimacy. The effectiveness of policing is dependent on public perceptions of the legitimacy of police actions (Tyler, 2004). Legitimacy is the public belief that there is a responsibility and obligation to voluntarily accept and defer to the decisions made by authorities (Tyler, 2006). Recent studies suggest that, when procedural justice approaches are used by the police, citizens will not only evaluate the legitimacy of the police more highly, they will also be more likely to obey the law in the future (Paternoster, Brame, Bachman, & Sherman, 1997). Advocates of focused deterrence strategies argue that targeted offenders should be treated with respect and dignity (Kennedy, 2008, 2011), reflecting procedural justice principles. The Chicago PSN strategy, for instance, sought to increase the likelihood that the offenders would “buy in” and voluntarily comply with the pro-social, anti-violence norms being advocated by interacting with offenders in ways that enhance procedural justice in their communication sessions (Papachristos et al., 2007).
The available scientific evidence on the violence reduction value of focused deterrence strategies had been previously characterized as “promising,” but “descriptive rather than evaluative” (Skogan & Frydl, 2004, p. 241) and as “limited,” but “still evolving” (Wellford, Pepper, & Petrie, 2005, p. 10) by the U.S. National Research Council’s Committee to Review Research on Police Policy and Practices and the Committee to Improve Research Information and Data on Firearms, respectively. A recently completed Campbell Collaboration systematic review identified ten focused deterrence evaluations (Braga & Weisburd, 2012); eight of these evaluations were completed after the National Research Council reports were published. It is important to note here that none of the eligible studies used randomized controlled experimental designs to analyze the impact of focused deterrence on crime; rather, all ten eligible studies used quasi-experimental designs. Nevertheless, a better-developed base of scientific evidence then existed to assess whether violence prevention impacts are associated with this approach.
There is consensus among those who advocate for evidence-based crime policy that systematic reviews are an important tool in this process. Formed in 2000, the Campbell Collaboration Crime and Justice Group aims to prepare and maintain systematic reviews of criminological interventions and to make them electronically accessible to scholars, practitioners, policy makers, and the general public (Farrington & Petrosino, 2001; see also The Campbell Collaboration). As part of the Campbell Collaboration’s efforts to build a scientific knowledge base on effective crime prevention practices, a systematic review has been conducted on an ongoing basis on the crime prevention effects of focused deterrence programs (Braga & Weisburd, 2012). The most recent iteration of the Campbell review found that focused deterrence programs were associated with significant crime reductions, with similar impacts generated by gang and criminally active groups, DMI, and individual offender programs alike.
Nine of the ten evaluations of “pulling levers” focused-deterrence programs included in the review found significant crime control benefits (Braga & Weisburd, 2012). While the authors did report a small but positive reduction in gunshot wound incidents, only the evaluation of Newark’s Operation Ceasefire did not report any discernible crime prevention benefits generated by the violence reduction strategy (Boyle, Lanterman, Pascarella, & Cheng, 2010). Evaluations of focused deterrence strategies targeting gangs and criminally-active groups reported large statistically significant reductions in violent crime, including a 42% reduction in gun homicides in Stockton (Braga, 2008), a 35% reduction in homicides of criminally active group members in Cincinnati (Engel, Corsaro, & Skubak Tillyer, 2010), a 34% reduction in total homicides in Indianapolis (McGarrell et al., 2006), and noteworthy short-term reductions in violent crime in Los Angeles (Tita et al,. 2004).
The two DMI evaluations also reported statistically significant crime reductions. In Nashville, the drug market intervention generated a 55% reduction in illegal drug possession incidents (Corsaro & McGarrell, 2009). In Rockford, the drug market intervention generated a 22% reduction in non-violent offenses (Corsaro, Brunson, & McGarrell, 2010). While Newark’s strategy did not generate statistically significant crime control gains when high-rate offenders were targeted, the Chicago PSN intervention, the other program focused on individuals described earlier, was associated with a 37% reduction in homicide (Papachristos et al., 2007).
More Recent Evidence
The available program evaluation evidence on the crime reduction impacts of focused deterrence programs has continued to grow since the completion of the latest version of the Campbell focused deterrence review. These new studies are characterized by increasingly more rigorous evaluation designs (Braga & Weisburd, 2014). Beyond the evaluations of the revitalized Boston Ceasefire program (e.g., Braga et al., 2014), three recently completed evaluations of gang focused deterrence programs implemented in Chicago, New Orleans, and New Haven also revealed significant reductions in violence associated with the approach. Papachristos and Kirk (2015) evaluated Chicago’s Group Violence Reduction Strategy (GVRS), a gun violence reduction program that delivers a focused-deterrence and legitimacy-based message to gang factions through a series of hour-long call-ins. For treated gang factions, they found the Chicago GVRS generated a 23% reduction in overall shooting behavior and a 32% reduction in gunshot victimization in the year after treatment compared with similar factions. Corsaro and Engel (2015) found that the New Orleans GVRS was associated with significant reductions in gang homicide, young black male homicide, and firearm violence. New Orleans homicide reductions were also found to be distinct from homicide trends in six similarly violent cities. Finally, Sierra-Arevalo, Charette, and Papachristos (2015) found the “Project Longevity” GVRS resulted in significant reductions in New Haven homicide and shooting trends relative to trends in nearby Hartford, Connecticut.
This growing body of research has led to an emerging policy consensus, especially on the first and most broadly implemented and evaluated violence-prevention focused deterrence strategies. Abt and Winship (2016), in a recent review to identify effective strategies for reducing community violence that included over 1,400 studies, found that focused deterrence programs had the largest direct impact on crime and violence, of any intervention in their report. Similarly, a systematic review by Wong, Gravel, Bouchard, Morselli, and Descormiers (2012), of strategies to control street gangs, revealed that focused deterrence was the most consistently effective solution to gang-related delinquency. These reports, placed alongside the recent evaluation results discussed above, have prompted strong policy endorsements. For instance, given the strong findings in New Orleans and Chicago, Land (2015, p. 515) recommended that police departments should incorporate this approach: “Such programs should be in the programmatic array of departments … Let the focused deterrence programs and related policing strategies roll, with eternal vigilance to maintain their effectiveness.”
The Prospects of Focused Deterrence in Improving Police-Community Relations
Policing communities, especially minority communities, always involves a delicate balance (Meares & Kahan, 1998). On the one hand, research suggests that the police benefit from the general willingness of community members to cooperate with them to report crimes, identify criminals, assist in investigations, and address conditions that might facilitate crime (Moore, 1992; Reisig, 2010; Tyler & Fagan, 2008). On the other hand, effective policing invariably involves tactics that bring the police into close and regular contact with community residents. This contact can be viewed by community residents, particularly minority residents, as intrusive and unwarranted, leading citizens to doubt whether the police respect their rights and care about their wellbeing (Brunson & Weitzer, 2009; Carr, Napolitano, & Keating, 2007). Whether or not individuals have personal contact with police officers, their perceptions of the legitimacy of police have consequences for police effectiveness (Tyler, 2004, 2006). Policing is far more difficult without the support of the public. Therefore, police effectiveness is influenced by the consequences of different tactical and policy choices for their legitimacy.
Police legitimacy is regarded as a view among the members of the communities involved that police play an appropriate role in making and implementing rules governing public conduct (Sunshine & Tyler, 2003; Tyler & Huo, 2002). While there are many factors that influence police legitimacy (e.g., see Bottoms & Tankebe, 2012), police departments need to develop, implement, and sustain crime control practices that are both fair and effective. As suggested by the National Research Council’s Committee to Review Research on Police Policy and Practices, “policing that is perceived as just is more effective in fostering a law-abiding society, and that success in reducing crime enhances police legitimacy” (Skogan & Frydl, 2004, p. 2). More recently, the President’s Task Force on 21st Century Policing (2015, p. 42) noted that “law enforcement’s obligation is not only to reduce crime but also to do so fairly while protecting the rights of citizens.”
Focused deterrence strategies represent a relatively new crime reduction approach that holds great promise in reducing serious violence while improving strained relationships between minority neighborhoods and the police departments that serve them (Kennedy, 2011). A growing body of rigorous scientific evidence suggests these strategies do indeed generate noteworthy crime prevention gains (Braga & Weisburd, 2012). Focused deterrence programs seem well positioned to be regarded as fair and just crime reduction approaches (Brunson, 2015). First, community leaders, social service providers, and others are engaged in the planning, design, and execution of these violence prevention initiatives. Collaborative partnerships between police and community members improve the transparency of law enforcement actions and provide residents with a much-needed voice in crime prevention work. Second, through the use of analysis to identify the gangs and other criminally active groups central to violence, these programs are highly focused on very risky people rather than subjecting uninvolved individuals to indiscriminate enforcement. Third, during “call-in” communication sessions, targeted individuals are warned of the consequences associated with continued violent behavior and are advised to take advantage of services and opportunities being offered to them. In the eyes of community members, there is an inherent fairness in offering targeted offenders a choice and providing resources to support their transition away from violent behavior rather than simply arresting and prosecuting them.
Fourth, focused deterrence takes advantage of recent theorizing regarding procedural justice and legitimacy (Braga, 2012; Brunson, 2015). Studies suggest that when procedural justice approaches are used by the police, citizens will not only evaluate the legitimacy of the police more highly, they will also be more likely to obey the law in the future (e.g., see Paternoster et al., 1997). Advocates of focused deterrence strategies argue that targeted offenders should be treated with respect and dignity, reflecting procedural justice principles (Kennedy, 2011). The Chicago Project Safe Neighborhoods strategy, for instance, sought to increase the likelihood that the offenders would “buy in” and voluntarily comply with the pro-social, anti-violence norms being advocated by interacting with offenders in ways that enhance procedural justice in their communication sessions (Papachristos et al., 2007).
Effective violence reduction requires proactive law enforcement actions to address the high-risk people and high-risk places that generate the bulk of urban violent crime problems. However, there is no legitimate reason why police departments can’t be proactive while being fair and respecting the rights of citizens. As such, focused deterrence strategies represent an important addition to our knowledge base on police-led violence prevention programs that seem to strike the important balance between fairness and effectiveness.
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