Program Profile: Hot Spots Policing in the London Underground (London, UK)

This policing strategy was designed to deter crime on platforms in high-crime areas of the London Underground. The program is rated Promising. Platforms in the treatment areas had statistically significant reductions in calls for services and crime, relative to the control group, on patrol and nonpatrol days.

A Promising rating implies that implementing the program may result in the intended outcome(s).

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

A Promising rating implies that implementing the program may result in the intended outcome(s).

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

Program Goals and Theory

Hot-spot police patrol was a policing strategy used to deter crime in high-crime areas on platforms of the London Underground train stations from mid-September 2011 through mid-March 2012. The premise behind the intervention was that patrols would act as a deterrent because people would be less likely to commit an offense in the presence of a police officer for fear of detection and, ultimately, punishment. Past research suggests this is attributable to spatiotemporal local deterrence mechanisms (Koper 1995).

Program Components

The London Underground is the public transportation system for the city of London. Each station in the London Underground railway has multiple platforms. Each platform offers only one direction of travel per track. At least two walled-off chambers exist in most stations: one for the trains going in one direction and one for trains going in the other (e.g., westbound or eastbound). If police are present on one platform, they cannot be seen on the other.

Twenty uniformed officers were selected and trained to conduct foot patrols on platforms in the targeted hot spots (if uniformed officers left due to normal turnover, they were replaced with other trained uniformed officers). Uniformed officers usually patrolled on foot in teams of two. The officers patrolled the platforms during the “hot hours” and “hot days” for the targeted platforms, which were Wednesdays through Saturdays between 3 p.m. and 10 p.m.

Each two-person “patrol unit” was responsible for three to five hot spots, depending on the traveling distance between their assigned hot spots. The patrol units were asked to attend to the hot spots four times on each assigned day for 15 minutes at a time and to attend the hot spots in a random or unpredictable order to avoid predictability of visits. Additionally, they were encouraged to engage with members of the public and avoid standing idle on the platforms. The officers were not tasked to problem-solve, conduct community policing in the classic sense, or target their efforts on any particular crime category. Immediately after each patrol team’s 15-minute visit, the officers boarded a train and traveled to the next platform. Each patrol team was debriefed daily by the sergeants.

Study

Ariel, Sherman, and Newton (2020) conducted a randomized controlled trial of hot-spots police patrols on the previously never-patrolled, track-level platforms of the London Underground (the rapid transit system of London). Each station in the London Underground railway has multiple platforms. To determine platforms eligible for inclusion in the study, all London Underground platforms were rank-ordered according to the level of crime they experienced in 12 months. The study excluded platforms that experienced fewer than two crimes per year, stations that were targeted and routinely patrolled by special “Hub Teams,” and platforms that were located too far away (45 minutes or more) from other stations. Hot spots were defined and located using a list of victim-generated “hard crimes” such as violence, antisocial behavior against others, and criminal damage (see Weisburd and Green 1995). Finally, a list of 115 eligible hot-spots platforms with a mean of greater than 4.72 crimes per year was created using targeting analysis. Random assignment was used to allocate the 115 eligible platforms to the treatment or control condition.

The experiment was in operation for 6 months, from mid-September 2011 through mid-March 2012, with comparisons to the same months of the previous year (2010–11). Fifty-seven of the London Underground’s 115 highest-crime platforms were randomly assigned to receive foot patrol by officers. The treatment platforms received foot patrol in 15-minute doses, four times a day, during 8-hour shifts on 4 days a week for 6 months. By the end of the experiment, there were 23,272 police arrivals at the treatment hot spots over 26 weeks. Fifty-eight of the London Underground’s highest-crime platforms were randomly assigned to the control condition. The control platforms did not receive patrols in hot spots and lacked any prior treatment at baseline.

During the baseline period, the sample stations had 6,052 calls for service and 4,471 crimes. A total of 2,834 calls for service were identified for the treatment hot spots, and 3,218 calls for service were identified for the control hot spots during the baseline period. A total of 2,079 crimes were identified for the treatment hot spots, and 2,392 crimes were identified for the control hot spots during the baseline period. No statistically significant pretreatment differences were found between treatment and control conditions for the eight comparisons examined in this study.

The outcome measures of interest were all calls for service to the police (“999 calls”) and all reported crimes within the participating hot spots during the 6 months of the experiment (2011–12) and for the 6 months in the (baseline) year before the experiment (2010–11). Data were then broken into eight outcome variations, reflecting the “types” of deterrence to be tested in the experiment: 1) crime on platforms only, on patrol days, during patrol hours; 2) crime on platforms only, on patrol days, during nonpatrol hours; 3) crime on platforms only, on nonpatrol days, during patrol hours; 4) crime on platforms only, on nonpatrol days, during nonpatrol hours; 5) calls for service on platforms only, on patrol days, during patrol hours; 6) calls for service on platforms only, on patrol days, during nonpatrol hours; 7) calls for service on platforms only, on nonpatrol days, during patrol hours; 8) calls for service on platforms only, on nonpatrol days, during nonpatrol hours. London Underground’s detachment of the British Transport Police provided crime and calls for service data.

The researchers used a pretest–posttest, control-group design to assess the impact of the treatment on the outcomes of interest. Specifically, generalized linear models were used to assess the differences between experimental and control hot spots in regard to citizen-generated calls-for-service and citizen-reported crime incident counts. Since the dependent variables were count variables, Poisson regression modeling was employed to estimate the multivariate models. The authors used Bayesian Information Criteria values to compare models. Based on the results of the models, the authors computed estimated marginal means, which provide the mean responses for each factor, and adjusted for the baseline scores. The means were then converted into standardized mean differences (Cohen’s d values), and the outcomes were then presented in forest plots. The authors did not conduct subgroup analyses.

A member of the research team (Ariel, Sherman, and Newton 2020) held monthly half-day meetings with all the officers, sergeants, and senior officers, during which the importance of treatment fidelity was communicated. During these “motivational debriefs,” the researcher provided feedback to officers about particular noteworthy incidents, crime figures during the previous month, and treatment dosage data. The assignments summed to 416 visits per hot spot over 6 months. The total dosage in the 58 treatment hot spots was about 5,000 hours.

Additionally, several steps were taken in structuring the treatment to limit “spillover” attributable to police presence: 1) shifts always began at the British Transport Police main offices, requiring no police presence on control platforms; 2) no station had both a treatment and a control platform; 3) treatment officers moved between the treatment hot spots by traveling on the trains, although they had to walk through a nearby station to get to and from a platform at the beginning and end of each shift; and 4) the officers were asked (without disclosure of the location of control platforms) to follow pathways that bypassed the control platforms in their transit between treatment platforms, to avoid spillover effects (Ariel, Sherman, and Newton 2020).

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

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

Koper, Christopher S. 1995. “Just Enough Police Presence: Reducing Crime and Disorderly Behavior by Optimizing Patrol Time in Crime Hot Spots.” Justice Quarterly 12(4):649–72.

Weisburd, David L., and Lorraine A. Green. 1995. “Policing Drug Hot Spots: The Jersey City Drug Market Analysis Experiment.” Justice Quarterly 12(4):711–35.

Following are CrimeSolutions-rated programs that are related to this practice:

Hot Spots Policing

Hot spots policing strategies focus on small geographic areas or places, usually in urban settings, where crime is concentrated. Through hot spots policing strategies, law enforcement agencies can focus limited resources in areas where crime is most likely to occur. This practice is rated Effective for reducing overall crime and rated Promising for reducing violent, property, public order, and drug and alcohol offenses.

Evidence Ratings for Outcomes

	Crime & Delinquency - Multiple crime/offense types
	Crime & Delinquency - Violent offenses
	Crime & Delinquency - Property offenses
	Crime & Delinquency - Public order offenses
	Crime & Delinquency - Drug and alcohol offenses

Geographically Focused Policing Initiatives

Geographically focused policing initiatives increase the presence and visibility of police officers at specific high-crime locations to significantly reduce crime and disorder. This practice is rated Promising for reducing crime in treatment areas relative to control areas.

Evidence Ratings for Outcomes

Crime & Delinquency - Multiple crime/offense types

Why might a practice's outcome ratings differ from the ratings of specific programs encompassed by that practice?