DOES WHAT POLICE DO AT HOT SPOTS MATTER? THE PHILADELPHIA POLICING TACTICS EXPERIMENT*

“Opportunity theories (Brantingham and Brantingham, 1991 [1981], 1993; Cohen and Felson, 1979; Felson, 1987) emphasize that the characteristics of places structure the routine activities of individuals and produce criminogenic combinations of of-fenders, targets, and guardianship levels at certain…”

“Incidence rate ratios (IRRs) are exponentiated β coefficients and reflect, after multiplying the difference between the IRR and 1 by 100, the expected percentage change in the predicted count of the outcome variable (Rabe-Hesketh and Skrondal, 2012).”

“…the OF tactic is based on the criminological axiom that a small percentage of offenders is responsible for a disproportionate amount of crime (Esbensen et al., 2010; Wolfgang, Figlio, and Sellin, 1972); however, the success of the OF treatment also has several possible practical explanations.”

“Repeated-measures multilevel models are appropriate for experimental study designs (Bryk and Raudenbush, 1987; Raudenbush and Bryk, 2002).”

“When community members perceive that police actions are fair, they are more likely to be more satisfied with and have confidence in police services, follow the law, and help police fight crime (Reisig and Lloyd, 2009; Taylor and Lawton, 2014; Tyler, 1988, 2004).”

“When community members perceive that police actions are fair, they are more likely to be more satisfied with and have confidence in police services, follow the law, and help police fight crime (Reisig and Lloyd, 2009; Taylor and Lawton, 2014; Tyler, 1988, 2004).”

“Using these tools, researchers have demonstrated that crime is concentrated in particular microlevel places, such as street segments (Weisburd et al., 2004), intersections (Taniguchi, Ratcliffe, and Taylor, 2011), and addresses (Pierce, Spaar, and Briggs, 1986; Sherman, Gartin, and Buerger, 1989),…”

“POP represents a shift from the standard model of policing (Weisburd and Eck, 2004) to a proactive approach that emphasizes identifying and solving problems (Goldstein, 1979, 1990).”

“Using these tools, researchers have demonstrated that crime is concentrated in particular microlevel places, such as street segments (Weisburd et al., 2004), intersections (Taniguchi, Ratcliffe, and Taylor, 2011), and addresses (Pierce, Spaar, and Briggs, 1986; Sherman, Gartin, and Buerger, 1989), and that crime level…”

“Of course, incarcerating prolific offenders is likely to have some incapacitative effects on crime rates as well (Blumstein, Cohen, and Nagin, 1978).”

“The first biweekly observation ( t 0 ) served as the referent (Twisk, 2003).”

“Given the precedent established in the hot spots policing evaluation literature (Braga and Bond, 2008; Braga et al., 1999; Weisburd and Green, 1995a, 1995b; Weisburd et al., 2006), the field researchers were instructed to create buffer areas extending roughly two blocks in all directions from each…”

“POP represents a shift from the standard model of policing (Weisburd and Eck, 2004) to a proactive approach that emphasizes identifying and solving problems (Goldstein, 1979, 1990).”

“Opportunity theories (Brantingham and Brantingham, 1991 [1981], 1993; Cohen and Felson, 1979; Felson, 1987) emphasize that the characteristics of places structure the routine activities of individuals and produce criminogenic combinations of of-fenders, targets, and guardianship levels at certain…”

“…precedent established in the hot spots policing evaluation literature (Braga and Bond, 2008; Braga et al., 1999; Weisburd and Green, 1995a, 1995b; Weisburd et al., 2006), the field researchers were instructed to create buffer areas extending roughly two blocks in all directions from each…”

“We could uncover only one study that applied a rigorous qualitative methodology to capture the types of actions undertaken during a POP evaluation (Braga and Bond, 2008).”

“Recent empirical evidence suggests immediate spatial displacement is less of a concern and a diffusion of crime control benefits is more likely (Guerette and Bowers, 2009; Weisburd et al., 2006).”

“The Philadelphia Police Department’s automated system achieves geocoding hit rates in excess of 98 percent, so the data are suitable for spatial data analysis (Ratcliffe, 2004).”

“Durlauf and Nagin (2011) hypothesized that strategically shifting resources from pris-ons to police to conduct hot spots policing can simultaneously produce crime reductions while reducing prison populations.”

“…segments (Weisburd et al., 2004), intersections (Taniguchi, Ratcliffe, and Taylor, 2011), and addresses (Pierce, Spaar, and Briggs, 1986; Sherman, Gartin, and Buerger, 1989), and that crime levels often vary from street to street (Groff, Weisburd, and Yang, 2010; Weis-burd, Groff, Yang, 2012).”

“Focusing resources on small, high-crime places has become widely known as “hot spots policing” (Braga, 2001; Weisburd and Braga, 2003).”

“This development has spurred an evolution in policing from random patrol (Weisburd and Eck, 2004) to focusing police resources on high-crime places (Sherman, 1997; Sher-man and Weisburd, 1995).”

“When community members perceive that police actions are fair, they are more likely to be more satisfied with and have confidence in police services, follow the law, and help police fight crime (Reisig and Lloyd, 2009; Taylor and Lawton, 2014; Tyler, 1988, 2004).”

“Evaluations of multiple tactics using robust experimental designs are scarce (for exceptions, see Braga and Bond, 2008; Taylor, Koper, and Woods, 2011).”

“The WDQ is expressed mathematically as follows: This quotient can be interpreted in terms of the success of the intervention as well as of whether displacement or a diffusion of benefits occurred (Bowers and Johnson, 2003: 286).”

“Cumulative evidence suggests that concentrating police resources in small areas can reduce crime (Braga, Papachristos, and Hureau, 2012; Lum, Koper, and Telep, 2011; Sherman, 1997); however, little is known about which policing tactics are best suited for policing small areas (Telep and Weisburd,…”

“One study used automatic vehicle location data to demonstrate that police presence can be precisely measured without the expense of field observation (Telep, Mitchell, and Weisburd, 2014).”

“Veteran officers may have less interest in dealing with minor drug cases or simply perceive FP as a punishment and choose not to generate activity (Moskos, 2008).”

“Intelligence-led policing is a policing model that uses crime information and criminal intelligence within an operational framework to identify and focus police resources on problem areas and on prolific and serious criminals (Ratcliffe, 2008).”

“Therefore, focusing only on the most serious offenders in crime hot spots in theory reduces the likelihood that hot spots policing will produce “backfire effects” (Weisburd et al., 2011).”

“Despite recent steady reductions, Philadel-phia still has higher violent crime rates than most other large American cities (Zimring, 2011).”

“Most POP evaluations, however, suffer from weak designs (Weisburd and Eck, 2004; Weisburd et al., 2008).”

“In addition, our results indicate that by focusing police efforts on the problem people associated with the problem places, police can achieve significant crime reductions while avoiding negative community perceptions of their actions (Haberman et al., 2014; Ratcliffe et al., 2012).”

“…crime is concentrated in particular microlevel places, such as street segments (Weisburd et al., 2004), intersections (Taniguchi, Ratcliffe, and Taylor, 2011), and addresses (Pierce, Spaar, and Briggs, 1986; Sherman, Gartin, and Buerger, 1989), and that crime levels often vary from street to…”

“Future research combining technology with qualitative research methods has promise for improving our understanding of police activity (see Esbensen et al., 2011, for a multimethod framework for program evaluation).”

“…careful implementation, crime reductions can occur without the massive increases in pedestrian and car stops often found with saturation patrols; these outputs tend to produce many arrests that subsequently flood lo-cal jails, the court system, and the prison system (see Goldkamp and Vilcica, 2008).”

“POP asks police officers to conduct applied science to address problems (Eck, 2006).”

“…consistency of treatment design with treatment implementation) is far more challenging and has received less attention (Sherman and Weisburd, 1995; Sorg et al., 2014) because of the difficulty and expense of collecting data describing the specific activities undertaken while assigned to FP, OF,…”

“…the OF tactic is based on the criminological axiom that a small percentage of offenders is responsible for a disproportionate amount of crime (Esbensen et al., 2010; Wolfgang, Figlio, and Sellin, 1972); however, the success of the OF treatment also has several possible practical explanations.”

“…Foundation, 1981) found no significant differences among treatment and control beats for reported crime or official arrests; subsequent studies also failed to find an effect for crime incidents (Bowers and Hirsch, 1987; Esbensen and Taylor, 1984) or calls for service (Cordner, 1991; Pate, 1989).”

“…Foundation, 1981) found no significant differences among treatment and control beats for reported crime or official arrests; subsequent studies also failed to find an effect for crime incidents (Bowers and Hirsch, 1987; Esbensen and Taylor, 1984) or calls for service (Cordner, 1991; Pate, 1989).”

“Even so, initiatives using POP often have achieved measurable crime reductions (see Weisburd et al., 2010), especially when focused at small places (Clarke and Eck, 2005; Weisburd and Eck, 2004; Weisburd et al., 2008).”

“The 65 eligible studies included (1) Minneapolis Repeat Call Address Policing (RECAP) Program (Sherman et al. 1989a) (2) New York Tactical Narcotics Teams (Sviridoff et al. 1992) (3) St. Louis Problem-Oriented Policing in threeDrugMarket Locations Study (Hope 1994) (4) Minneapolis Hot Spots Patrol Program (Sherman and…”

“finding that the offender-focused approach was the most effective in reducing violent crime (Groff et al., 2015).”

“Braga, Hureau, and Papachristos (2014), Groff et al. (2014), and Papachristos and Kirk (2015) found significant effects of focused deterrence on violent crime.”

“We point readers to the experimental evaluation for further information on the design of the study and the results (Groff et al. 2015).”

“Besides, our finding is consistent with previous studies on security equipment with a focus on small places or groups of people in small places (Groff et al., 2015; Kinney et al., 2008; Kubrin et al., 2010; Long et al., 2018; Reid & Andresen, 2014; Sampson & Cohen, 1988).”

“…qualitative studies of this agency showed the JSO as willing and able to carry out proactive policing activities, evaluations, and innovations (see Groff et al. 2015; Harris Corporation and the Jacksonville Sheriff’s Office 2002; Taylor et al. 2011), and that proactivity is a concept that…”

“Recent reviews of the literature on hot spots policing, which includes a number of well-executed randomized experiments (Braga & Bond, 2008; Groff et al., 2015; Sherman & Weisburd, 1995), find that these efforts have generally been successful in reducing crime without displacing crime to adjacent…”

“For quite some time now, research has been interested in what officers do and how they patrol (Groff et al. 2015, Wuschke et al. 2018).”

“Although there is a possibility that due to diversion of resources to certain areas other (not targeted) neighborhoods might suffer, recent policing studies have found only very limited negative side-effects during focused interventions (Groff et al. 2015; Sidebottom et al. 2017).”

“As these tactics often focus on police-designated “hot spots” (Groff et al., 2015) in low-income communities, Black and brown Philadelphians are disproportionate recipients of involuntary police contact including unwarranted stops, frisks, and misconduct by police (ACLU, 2010; Goffman, 2015;…”

“While Ratcliffe et al. (2011) found that foot patrol generated significant crime reductions at hot spots, Groff et al. (2015) found that foot patrol was not associated with any changes in crime occurrence.”

“Explanations for crime have focussed on: NTE places deemed to have ‘too many’ licensed premises, those saturated with a high density of premises (Livingston, 2008; Pridemore & Grubesic, 2013); and, premises open ‘too long’, with concerns over the length of time premises can remain open for, based…”

“Although many types of police activities are helpful in managing hot spots, evaluation studies suggest that interventions grounded in problemoriented policing (POP) are generally most effective (Braga and Bond, 2008; Taylor et al., 2011; Braga et al., 2012; but see also Groff et al., 2015).”

“Knowing more about how different hot spot policing approaches affect public perceptions and attitudes would greatly inform research on best strategies to use in hot spots for enhancing crime prevention as well as police-community relations (Braga et al., 2019; Braga & Bond, 2008; Groff et al., 2015; Kochel et al., 201…”

“It also enables the mapping and display of crime incidents by visualizing crime trends and hot spots (Andresen 2011; Groff et al. 2015).”

“2014), but there is much less research on response dosage (Groff et al. 2015; Telep et al. 2014).”

“…leadership, the PPD has operated under a city-wide hot spots policing strategy, conducted two hot spots policing experiments in collaboration with academic researchers (Groff et al., 2015; Ratcliffe et al., 2011), and worked to improve the department’s crime and intelligence analysis capacity.”

“For example, many police agencies direct their officers to particular places at times when offenders are known to be active (e.g. Groff et al., 2015), which may result in officers being more likely to convert an opportunity to search someone into an actual search.”

“This oversight can lead to long-term risks, such as undermining police legitimacy and disrupting the lives of law-abiding citizens who live or work in those areas [43,44].”

“…or problem-oriented sites, the study was still able to conclude that the locations where an offender-focus strategy was implemented “ produced significant decreases in violent crime, with decreases in 42 percent for all violence and 50 percent for violent felonies ” (Groff et al. , 2015, p. 42).”

“Social control from criminal justice agencies • Hot Spots Policing (Groff et al., (2015).”

“The Weisburd and colleagues’ study and others like it (e.g., Groff et al., 2015; Groff, Weisburd, & Yang, 2010; Piza & O’Hara, 2014; Weisburd, 2015) support the premise that aggregate city crime rates and trajectories over time can be influenced by ‘‘microgeographic hot spots.’’”

“As noted by Groff and colleagues, these types of policing interventions can be difficult to implement consistently and measure effectiveness with an RCT framework (Groff et al., 2015), raising questions about the feasibility of maintaining an RCT of this type of intervention for a year across over 100 hot spots with p…”

“Lastly, enforcement activity may be a driver of temporal displacement activity, finding support for the influence of police activities and crime (Groff et al. 2015; Sorg et al. 2014; Telep et al. 2014) but given the small effect sizes the increases in enforcement 148 Journal of Research in Crime and Delinquency 59(1)”

“…in experimental and quasi-experimental studies of hot spots policing (Sherman and Weisburd, 1995; Braga and Bond, 2008; Braga et al., 2014; Groff et al., 2015; Blattman et al., 2017) disorder reduction (Braga and Bond, 2008; Branas et al., 2011; MacDonald et al., 2016; Branas et al.,…”

“For instance, Gill et al. (2017) examined Brooklyn Park, WA and found 50 percent of the city ’ s crime occurred at 2 percent of Brooklyn Park ’ s street segments, indicating lower street variability compared to other cities, such as Seattle (Groff, Weisburd, & Morris, 2009; Groff et al., 2015).”

“…concentrating police efforts in high crime areas, multiple strategies have been used (e.g., aggressive order-maintenance policing, offender-focused policing, situational interventions), with some receiving more support than others (A. Braga et al., 2012; Groff et al., 2015; Weisburd & Eck, 2004).”

“While some of the circumstances limiting these efforts in our study sites may have been unique (e.g., the COVID-19 pandemic), others have also documented the dif fi culty of implementing rigorous problem-solving in patrol work (e.g., Cordner & Biebel, 2005; Groff et al., 2015; Skogan et al., 1999).”

“Recent research suggests that combining people- and place-based strategies, such as focusing on prolific offenders in hotspot locations, holds significant promise for violence reduction (Groff et al., 2015; Uchida & Swatt, 2013).”

“Treatments tested to date include increases in foot or vehicle patrol, offender-focused apprehension programs, camera monitoring with directed patrol, drug enforcement operations, and problem-oriented policing strategies (Braga et al., 2019; Groff, 2015; Rosenfeld et al., 2014).”

“Some studies suggest that temporary deployment of patrol officers is best, while others suggest focused teams are more effective (Groff et al., 2015; Koper, 1995).”

“Despite this promise, the literature points to the challenge of implementation to see the potential full effect of hot spots policing and POP (Eck, 2006; Groff et al., 2015; Townsley et al., 2003).”

“This is an important limitation given that what officers do at crime hot spots matters for reducing violence in these places (Groff et al., 2015).”

“Third, focusing on specific offenders who are driving crime problems in hot spots (i.e., offender-focused policing) can reduce crime (Groff et al., 2015).”

“However, one major weakness of traditional systems is the dependence on historical data, implying that even though host spots could be visualized, law enforcement agencies could not respond in real time [3].”

“…2011; Curtin et al. 2007; D’Amico et al. 2002; De La Cruz 2016; Decker et al. 2007; Fleming and Grabosky 2009; Greasley and Smith 2017; Green 1984; Groff et al. 2014; Heller and Markland 1970; Johnson and Rhodes 2009; Maxfield 1982; Mazzerolle et al. 2002; Moore and Braga 2003; Sacks 2003; Sarac…”