MEASURING THE EFFECTS OF IMPROVED STREET LIGHTING ON CRIME

We consider Dr Marchant's criticisms of our systematic review and meta-analysis of the effects of improved street lighting on crime. We conclude that the Birmingham, Bristol and Dudley evaluations did provide evidence that improved lighting caused a decrease in crime. We also find that the conclusions of our meta-analysis hold up, even if we greatly increase the variance of our effect size measure. We conclude that existing evaluations of the highest methodological quality, when analysed together, show that improved lighting, on average, caused a significant 20-per-cent decrease in crime in experimental areas compared with comparable control areas.