Does the Police-Monitored CCTV Scheme Really Matter on Crime Reduction? A Quasi-Experimental Test in Taiwan's Taipei City.

Although numerous public closed-circuit television (CCTV) initiatives have been implemented at varying levels in Taiwan's cities and counties, systematic evaluations of these crime reduction efforts have been largely overlooked. To address this void, a quasi-experimental evaluation research project was designed to assess the effect of police-monitored CCTV on crime reduction in Taipei City for a period of 54 months, including data for both before and after camera installation dates. A total of 40 viewsheds within a 100-m (328 feet) radius were selected as research sites to observe variations in four types of crime incidents that became known to police during the January 2008 to June 2012 period. While crime incidents occurring in both the target and control sites were reduced in frequency after CCTV installation, results derived from time-series analysis indicated that the monitoring had no significant effect on the reduction of property crime incidents with the sole exception of robbery. With respect to the effects of comparing target and control sites, the average Crime Reduction Quotient (CRQ) was 0.36, suggesting that CCTV has an overall marginal yet noteworthy influence. Viewed broadly, however, the police-installed CCTV system in Taipei City did not appear to be as efficient as one would expect. Conversely, cameras installed in some observation sites proved to be significantly more effective than cameras in other sites. As a recommendation, future researchers should identify how particular micro-level attributes may lead to CCTV cameras working more effectively, thereby optimizing location choices where monitoring will prove to be most productive.