Crime Time: How Ambient Light Affect Criminal Activity

Abstract

We study the effect of daylight on crime. We take advantages of Daylight Saving Time policy (DST) which imposes exogenous variations in daylight exposure at specific hours of the day. We use a rich administrative database managed by the Chilean national police which is a very centralized agency and collects detailed information regarding each crime incident. We find a significant 20% decrease in property crimes associated to the DST transition that increases in one hour the amount of sunlight for the 7-9PM period. Consistently we find a similar increase in crime when DST transition sharply decreases the daylight exposure for the same period of the day. Our findings are also consistent under two strategies that rely on different identification assumptions: sharp regression discontinuity design and a diff-in-diff regression analysis. When we analyze heterogenous responses for different crime categories our results suggest that most of the variation is driven by robbery which decreases 30% during the evening hours of the day. Importantly, our results are robust to the inclusion of a particular demand-side response such as the time commuting pattern of the population, and we find no substantial short-term displacement for a particular period of the day.

Keywords: Rational Choice Theory of Crime, Daylight Saving Time, Criminal Behavior

JEL Classification: K42, R41, D01