Examining the Association between Heat Exposure and Crime in Cities across the United States: A Scoping Review.

Growing evidence suggests exposure to high temperatures may result in increased urban crime, a known driver of health and health inequity. Theoretical explanations have been developed to describe the heat-crime relationship without consensus yet achieved among experts. This scoping review aims to summarize evidence of heat-crime associations in U.S. cities. Further examination of empirical and translational inconsistencies in this literature will ensure future studies of urban heat-crime relationships in the U.S., and their policy impacts are informed by a thorough understanding of existing evidence. We performed a comprehensive literature search of empirical studies on heat-crime relationships in U.S. cities published between January 2000 and August 2023. The included studies were qualitatively synthesized based on operationalized exposures, outcomes, covariates, methodologies, theoretical framing, and policy implications. In total, 46 studies were included in this review. Most studies (93%) reported significant, positive associations between urban heat exposure and both violent and non-violent crime outcomes. The shape and strength of these associations varied based on operational definitions of urban heat exposures, crime outcomes, and relevant covariates in employed methods. We also found inconsistencies in the theoretical explanations and policy implications reported across studies. Climate-driven extreme heat events are projected to increase in frequency and severity. Our findings underscore the urgency of refining the understanding and translation of the complex relationship between urban heat and crime. In this review, we highlight opportunities to improve the methodological quality and responsible policy translation of future research in U.S. cities, which has implications for research globally.