Micro Places – Groff et al. (2015) (Foot patrol)

Study Reference:

Groff, E. R., Ratcliffe, J. H., Haberman, C. P., Sorg, E. T., Joyce, N. M., Taylor, R. B. (2015). Does what police do at hot spots matter? The Philadelphia Policing Tactics Experiment. Criminology, 53(1), 23-53.

Location in the Matrix; Methodological Rigor; Outcome:

Micro places; General; Proactive; Very Rigorous; No evidence of an effect

What police practice or strategy was examined?

This study examined three different approaches to hot spots policing – foot patrol, problem-solving, and offender-focused strategies. Hence, this study is reported three times in the Matrix, and the focus for this summary is the foot patrol experiment. Foot patrol consisted of officers walking foot in hot spot areas for a minimum of 8 hours per day, 5 days per week, for 12 weeks. District Captains given discretion to determine how many officers would patrol, which days and times officers would patrol, and other operational decisions.

How was the intervention evaluated?

A total of 81 high crime areas were identified for the overall study. 27 of these areas were selected as amenable for each condition (thus, there were 27 areas selected for the foot patrol portion of this study). Of these 27 areas, 20 areas were randomly assigned to receive foot patrol and 7 acted as control sites that received usual police services. The researchers examined two separate violent crime outcome measures: all violent crime and violent street felonies, both taken from the Philadelphia Police Department’s crime incident database.

What were the key findings?

The foot patrol approach did not result in statistically significant reductions in violent crime relative to control areas.

What were the implications for law enforcement?

The authors suggest a possible reason for the findings are insufficient dosage and diversity of foot patrol in the hot spots. To provide the best representation of how hot spots policing tactics would be implemented under normal conditions within a large urban police department, researcher involvement was minimal during the implementation; because of this the authors were unable to determine how much dosage levels affected the results of the study. The police department’s desire to deliver treatment to 60 places might have made it more difficult to find an effect because it required the inclusion of lower crime hot spots and lowered uniformity of hot spots within each tactic. Additionally, foot patrol officers in this experiment spent only half the amount of time in hot spots than those who were part of the initial Philadelphia Foot Patrol Experiment and the hot spots they patrolled were physically larger.

Where can I find more information about this intervention, similar types of intervention, or related studies?