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New study of effect of CCTV cameras on crime in Newark, NJ, highlights value of longer-term evaluations

Place-based crime-prevention interventions have been critiqued for the short duration of reductions in crime they produce. In a new study, researchers evaluated the long-term impacts of a large public closed-circuit television (CCTV) surveillance project in Newark, NJ. The study found that the project was associated with reduced auto thefts three to four years after cameras were installed, effects that might not have been found if the evaluation ended after just one or two years.

The study, by researchers at Northeastern University's Crime Prevention Lab and AH Datalytics, in Criminology & Public Policy.

"If researchers don't carry out studies of longer durations, we cannot know for sure if the effects of interventions persist, decay, or even strengthen," explains Eric Piza, Lipman Family professor of criminology and criminal justice at Northeastern University, who led the study.

The use of CCTV cameras has risen significantly in the United States and other western countries over the last 20 years. Most studies evaluating the impacts of such surveillance on crime have been short in duration, with the average lasting only 17 months, which may be inadequate for understanding the longer-term effects of such projects.

In this study, researchers examined the short-term (1–2 years), intermediate-term (3–4 years), and long-term (9–11 years) impacts on violent and serious property crimes of a large CCTV surveillance project carried out in several public places in Newark, NJ. The Newark Police Department installed a public video surveillance system in 2008 and had nearly 150 individual surveillance cameras set up by 2010.

The project was associated with a statistically significant reduction of auto theft in the intermediate term. The CCTV project's effect on auto theft grew from approaching significance to statistically significant between the short and intermediate term. These so-called sleeper effects suggest that an extended period was necessary for the project to be associated with auto theft deterrence. The study also identified potential displacement effects, with displacement of robbery in the short term and theft from cars in the long term approaching statistical significance.

"Studies that last longer may reveal desirable effects that emerge after a program has been operating for a while or even changes in the direction of the effects," notes Brandon Welsh, the Dean's professor of criminology and criminal justice at Northeastern University, who coauthored the study.

"Based on our findings, policymakers need to understand that research that assesses short-term impacts may fail to detect nuanced effects that are relevant for decision-making."