Crime Seasonality across Multiple Jurisdictions in British Columbia, Canada

Abstract

Seasonal changes in crime have been documented since the mid-1800s, but no definitive consensus has been reached regarding universal annual patterns. Researchers also tend to focus on a single city over a particular time period, and, due to methodological differences, studies can often be difficult to compare. As such, this study investigates the seasonal fluctuations of crime across eight cities in British Columbia, Canada, between 2000 and 2006. Uniform Crime Report data, representing four crime types (assault, robbery, motor vehicle theft, and break and enter) were used in negative binomial or Poisson count models and regressed against trend, weather, and illumination variables. Results suggest that temperature changes impacted assault levels, few weather variables affected the occurrence of robberies, and fluctuations in property crime types were variable across the cities. Moreover, rain and snow had a deterrent effect on crime in cities that were not used to such weather conditions. These findings imply that (a) changes in weather patterns modify peoples’ routine activities and, in turn, influence when crime is committed; (b) universal crime seasonality patterns should not be assumed across all cities; and (c) crime seasonality should be studied at a disaggregate or crime-specific level.