Improved street lighting and crime prevention

This article reports on a systematic review-incorporating meta-analytic techniques-of the effects of improved street lighting on crime. Studies were included if they had before-and-after measures of crime in experimental and control areas. Eight American evaluation studies met the criteria for inclusion, and their results were mixed. Four studies found that improved street lighting was effective in reducing crime, while the other four found that it was not effective. However, five more-recent British evaluation studies showed that improved lighting led to decreases in crime. In two studies, the financial savings from reduced crimes greatly exceeded the financial costs of the improved street lighting. A meta-analysis found that the 13 studies, taken together, showed that improved lighting led to reductions in crime. The overall reduction in crime after improved lighting was 20% in experimental areas compared with control areas. Since nighttime crimes did not decrease more than daytime crimes, a theory focusing on the role of street lighting in increasing community pride seems more plausible than a theory focusing on increased surveillance. Future research should be designed to test the main theories of the effects of improved lighting more explicitly and should measure crime using police records, surveys of victims, and self-reports of offending.