Air pollution and criminal activity: microgeographic evidence from Chicago

A growing literature documents that air pollution adversely impacts health, productivity, and cognition. This paper provides the first evidence of a causal link between air pollution and aggressive behavior, as documented by violent crime. Using the geolocation of crimes in Chicago from 2001-2012, we compare crime upwind and downwind of major highways on days when wind blows orthogonally to the road. Consistent with research linking pollution to aggression, we find that air pollution increases violent crime on the downwind sides of interstates. Our results suggest that pollution may reduce welfare and affect behavior through a wider set of channels than previously considered.