Vertical Markets

Platform patrol experiment

by Mark Rowe

The total crime prevention benefit of police patrols may be greater when they are absent than when they are present, according to a criminological experiment that sent regular police patrols to platforms.

Researchers from Cambridge University’s Institute of Criminology worked with the British Transport Police (BTP) to conduct the experiment across six months in 2011-2012. The findings have been published in the journal Criminology.

The criminologists identified 115 London platforms where reported crime was highest. They randomly allocated 57 of these platforms to four daily ‘doses’ of patrols – two officers on foot for quarter of an hour – four days a week, and compared the effects to the remaining ‘untreated’ platforms. Patrolled platforms saw a drop from 88 crimes in the preceding six months to 63 crimes on the same platforms during the six months of the experiment. In the same time periods, crimes on platforms without regular patrols increased from 64 to 74.

A total of 3,549 calls to police from platforms came from stations without patrols, compared to 2,817 in the stations receiving a policing ‘dosage’ – a relative difference of 21pc. Researchers also found that patrols on platforms did not simply ‘displace’ the crimes. Instead, the overall pattern showed crime going down in all parts of the stations – not just on platforms – relative to ‘control’ stations.

They found that near all the reduction in crime and calls for assistance occurred when these police patrols were absent – some 97 per cent of the measured effect. The criminologists have dubbed this the “London Underground paradox”.

Study co-author Prof Lawrence Sherman said: “In the London Underground experiment we see a huge residual effect of brief appearances by patrolling officers after they leave.

“This phantom effect suggests that crime declines when potential offenders are apprehensive about a possible police presence based on recent patrolling patterns – even when there are no police in the vicinity. In London stations, it may be that more professional kinds of offenders are particularly sensitive to changes in police presence, such as pickpockets and distraction thieves.”

“The London Underground paradox could have implications for debates on police priorities in an age of austerity, such as the benefits of investigating past crimes compared with the benefits of preventing future crimes,” Sherman said.

London Underground’s crime is mostly on the trains and in concourse areas. Crime on platforms constitute 11pc of the total, and historically platforms have not had regular police patrols. Hence, say the academics, platforms offered an opportunity to conduct an experiment on spaces within a major metropolis that had never seen proactive police presence – ideal for gauging patrol effectiveness without previous ‘contamination’, say researchers.

The first author Dr Barak Ariel said: “Platforms are small, stable and confined places with finite entry and exit points. These characteristics make them optimal for measuring the localised deterrence effects of police patrols. We wanted to measure what happens when police patrols are introduced into an urban environment for the first time in over 150 years.”

The team targeted ‘hot spots’ – areas where crime is more concentrated, and preventative patrols can have greatest effect – by ranking stations based on the previous year’s crime rates, and including the top 115 of Greater London’s 270 stations in the experiment.

Researchers also narrowed the experiment’s focus based on ‘hot hours’ and ‘hot days’. Previous data showed the sample platforms saw more crime and calls to police from Wednesday to Saturday between 3pm and 10pm. Some 20 uniformed BTP officers were selected and trained to work exclusively on patrolling the platforms of the ‘treatment’ stations during ‘hot’ days and hours. Each two-person unit was allocated between three and five stations, with platforms patrolled for 15 minutes four times a day.

Officers were asked to conduct these patrols in a random or unpredictable order within the ‘hot hours’, and encouraged to engage with the public while patrolling.

Police were most effective at preventing platform crime during periods and days when patrols were scheduled – but just 3pc of that reduction came when officers were actually scheduled to patrol. The researchers also found ‘regional’ effects: crime in the rest of the station fell almost as much as crime on platforms during the four days when regular patrols were deployed.

Sherman said: “Our findings indicate that consistent patrols can cause large reductions in both crime and emergency calls in areas that have never before been proactively patrolled by police in this way. The more that uniformed police have been there, and the more recently, the less likely future crimes may be to occur.”

Picture by Mark Rowe; Baker Street.

Related News

Newsletter

Subscribe to our weekly newsletter to stay on top of security news and events.

© 2024 Professional Security Magazine. All rights reserved.

Website by MSEC Marketing