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Program Profile: Philadelphia Policing Tactics Experiment: Offender-Focused Policing

Evidence Rating: Effective - One study Effective - One study

Date: This profile was posted on February 29, 2016

Program Summary

This is a proactive, hot spots policing tactic that focuses attention on repeat violent offenders operating in neighborhoods with high violent-crime rates. The program is rated Effective. Hot spots that received the treatment reported significantly fewer violent crimes and violent felonies relative to the control areas. However, citizens’ perceptions of crime and safety were not impacted by the intervention.

This program’s rating is based on evidence that includes at least one high-quality randomized controlled trial.

Program Description

Program Goals
The Philadelphia Policing Tactics Experiment was a randomized controlled field experiment that tested three approaches to hot spots policing: offender-focused (OF) policing, foot patrol, and problem-oriented policing. OF policing is a deterrence-based strategy targeting high-risk offenders. OF policing’s main goal is to reduce violence by increasing the risk of apprehension for an area’s most prolific offenders. Targeted offenders were identified by intelligence analysts based on data from several police departments. This tactic was implemented in 20 violent crime hot spots in Philadelphia, as part of a field experiment testing different policing tactics in small, high-crime areas.
Target Population
OF policing targets repeat violent offenders. During the Philadelphia Policing Tactics Experiment, individuals identified for increased police attention had long criminal histories. In addition, there was intelligence that suggested the identified offenders continued to engage in crimes and were active in criminal networks.
Program Activities
In Philadelphia, police departments collaborated with intelligence analysts from the Central Intelligence Unit to identify repeat violent offenders residing in violent hot spots. Analysts followed the tenets of intelligence-led policing, using data from multiple districts to compile a list of the highly active offenders living in or committing crimes in designated hot spots.
The selected individuals were subjected to increased police attention, including proactive questioning and surveillance. Officers assigned to OF policing aggressively patrolled the identified hot spots and made frequent contacts with the prolific offenders. The contacts ranged from making small talk with the known offenders to serving arrest warrants if the target offenders committed crimes. Some OF officers collaborated with local beat officers as well. In addition, some districts used flat-screen televisions in roll-call rooms to display photos and convey other intelligence on the target offenders to all law enforcement personnel in the district.
Key Personnel
OF policing involves collaboration between police departments and intelligence analysts. In Philadelphia, departments from neighboring districts contribute crime data to identify the most prolific offenders committing violent crimes in any part of the city. Additionally, officers assigned to patrol the violent crime hot spots and contact target offenders are members of the tactical operations squad. Officers assigned to the OF teams were known to be proactive, and they were exempt from answering radio calls while they were focused on monitoring the identified offenders.
Program Theory
OF policing is based on deterrence theory, which argues that swift, certain, and severe sanctions can deter crime. Increasing police attention toward certain prolific offenders increases their actual and perceived risk of apprehension should they commit a crime, and therefore discourages such behavior. This method of policing is based on the idea that a small number of highly active offenders is usually responsible for a large proportion of crime. In addition, focusing on high-crime areas allows police departments to allocate resources to areas that yield the most potential gains (Ratcliffe 2008; Groff et al. 2014; Kennedy 1997).

Evaluation Outcomes

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Study 1
Violent Crimes
Groff and colleagues (2015) found that areas in Philadelphia identified as crime hot spots that received offender-focused (OF) policing experienced a statistically significant decrease in violent crime. It was estimated that OF policing produced a 42 percent reduction in violent crime relative to the control areas that were patrolled as usual by police officers.
Violent Felonies
In addition, there was a statistically significant decrease in violent felony crimes. Violent felony counts were 50 percent lower in the OF policing areas compared with the control areas.
Study 2
Citizen Perceptions
Ratcliffe and colleagues (2015) reported no statistically significant differences in how citizens residing in hot spots viewed crime and disorder in their area before and after OF policing was implemented. Residents did not feel safer, perceive different amounts of crime or disorder, or view the police more positively or negatively.
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Evaluation Methodology

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Study 1
Groff and colleagues (2015) evaluated offender-focused (OF) policing as part of the Philadelphia Policing Tactics Experiment. The study involved evaluations of three tactical approaches employed in the experiment: foot patrol, problem-oriented policing, and OF policing. As part of the experiment, intelligence analysts identified 81 violent-crime hot spots within Philadelphia, and police commanders determined which one of the three tactical approaches would be most appropriate to employ at each hot spot. Commanders chose 27 hot spots for each of the three interventions. Hot spots in each of these groups were randomly assigned to treatment and control categories. With regard to the OF policing approach, 20 hot spots received OF policing for 12 weeks and seven hot spots served as control areas. These control areas received no additional police attention and officers patrolled as usual. The treatment and control areas were equivalent at baseline due to the randomization procedure.
The primary outcome of interest was change in violent crime during the intervention period, which was examined using repeated-measures multilevel models, controlling for seasonality and the size of the hot spot. Contrast coding was used to examine crime rates during the intervention period rather than before or after the tactics were instituted. Violent crime was measured in two ways: violent felonies and all violent crimes. Violent crimes included all homicides, robberies, and aggravated assaults (simple assaults were excluded). The Philadelphia Police Department provided official data on the number of violent crimes biweekly during the study period. Spatial displacement of violent crimes in areas surrounding the treatment hot spots was also measured.
Study 2
Ratcliffe and colleagues (2015) examined the extent to which the Philadelphia Policing Tactics Experiment (which included OF policing) influenced citizens’ perceptions of the police. The researchers administered mail surveys 90 days before the tactics were implemented and 90 days afterwards. The surveys gauged how OF policing, foot patrol, and problem-oriented policing altered perceptions of crime, safety, disorder, and satisfaction with the police in the 81 hot spots.

Any taxable residence within the hot spot was eligible to receive the survey. With regard to OF policing specifically, 1,830 surveys were sent to addresses in the 20 OF hot spots, as well as 1,855 surveys to residents in the control areas. A total of 152 surveys from OF hot spots and 159 from control areas were returned before the policing tactics were implemented. Post-intervention, 160 surveys were returned from the OF hot spots and 177 from control areas, amounting to a response rate of 9 percent. Due to high non-response bias, citizens who returned the surveys were likely not representative of all citizens in the intervention and control areas. Ordinary least squares (OLS) regressions were used to estimate the impact of the policing tactics on changes in community perceptions of crime, disorder, safety, and satisfaction with the police.

A limitation of this study was the inability to match survey responses to specific households before and after the policing tactics were implemented. The study authors suggested that it was unlikely that the responses were attained from the same residents at both times, making it difficult to know whether the dependent variables captured changes in perceptions or reflected the perceptions of two different groups at two different times.
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There is no cost information available for this program.
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Implementation Information

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The offender-focused (OF) component of the Philadelphia Policing Tactics Experiment was introduced during a meeting with the Philadelphia Police Department executive command staff, district commanders and officers assigned to implement OF strategies, the police department’s Central Intelligence Unit, and the research team.
To ensure that officers were complying with the OF components of the experiment, researchers viewed officers’ daily logs and incident reports to determine what activities they performed during the 12-week intervention. The incident reports provided lists of the repeat offenders that the officers were targeting and the number of times the targeted offenders were questioned. The research team also observed officers and conducted interviews to obtain additional information on their activities (Groff et al. 2015).
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Evidence-Base (Studies Reviewed)

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These sources were used in the development of the program profile:

Study 1
Groff, Elizabeth R., Jerry H. Ratcliffe, Cory P. Haberman, Evan T. Sorg, Nola M. Joyce, and Ralph B. Taylor. 2015. “Does What Police Do at Hot Spots Matter? The Philadelphia Policing Tactics Experiment.” Criminology 53: 21-53.

Study 2
Ratcliffe, Jerry H., Elizabeth R. Groff, Evan T. Sorg, and Cory P. Haberman. 2015. “Citizens’ Reactions to Hot Spots Policing: Impacts on Perceptions of Crime, Disorder, Safety, and Police.” Journal of Experimental Criminology 11: 393-417.
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Additional References

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These sources were used in the development of the program profile:

Kennedy, David M. 1997. “Pulling Levers: Chronic Offenders, High Crime Settings, and a Theory of Prevention.” Valparaiso University Law Review 31(2):449–84.
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Related Practices

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Following are practices that are related to this program:

Hot Spots Policing
Used by many U.S. police departments, hot spots policing strategies focus on small geographic areas or places, usually in urban settings, where crime is concentrated. The practice is rated Effective. The analysis suggests that hot spots policing efforts that rely on problem-oriented policing strategies generate larger crime reduction effects than those that apply traditional policing strategies in crime hot spots.

Evidence Ratings for Outcomes:
Effective - One Meta-Analysis Crime & Delinquency - Multiple crime/offense types

Focused Deterrence Strategies
Problem-oriented policing strategies that follow the core principles of deterrence theory. The practice is rated Promising. The evaluation found that focused deterrence strategies (also referred to as “pulling levers" policing) can reduce crime.

Evidence Ratings for Outcomes:
Promising - One Meta-Analysis Crime & Delinquency - Multiple crime/offense types
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Program Snapshot

Gender: Both

Race/Ethnicity: Black, Hispanic, White

Geography: Urban

Setting (Delivery): High Crime Neighborhoods/Hot Spots

Program Type: Community and Problem Oriented Policing, Violence Prevention, Hot Spots Policing, Specific deterrence

Targeted Population: Serious/Violent Offender, High Risk Offenders

Current Program Status: Not Active

Listed by Other Directories: Campbell Collaboration