Does tree canopy moderate the association between neighborhood walkability and street crime?

Abstract

Creating walkable places and increasing urban vegetation in neighborhoods have emerged as important planning strategies to promote health, social, and environmental benefits. Although past studies have found that walkability and tree canopy are associated with crime, little research has comprehensively examined how neighborhood walkability and tree canopy are associated with street crime. The current study fills this gap by analyzing the relationship among walkable access to amenities measured by Walk Score, urban tree canopy, and the five-year violent and property street crime rates (2014–2018) across an entire city. This study used the case of Austin, Texas to investigate the association exists between 1) neighborhood walkability and street crime and 2) tree canopy and street crime. We also assessed whether the association between neighborhood walkability and street crime was moderated by tree canopy. The first set of models based on a negative binomial regression showed that neighborhood walkability was positively associated with both violent and property street crime rates while tree canopy was inversely associated with violent and property street crime rates. The second set of models revealed a nonlinear relationship between neighborhood walkability and the street crime rate. The final set of models showed that tree canopy cover can moderate the relationship between street crime and neighborhood walkability, suggesting that tree canopy can somewhat offset the negative influence of walkable neighborhoods, such as crowdedness and noise, in relation to street crime. The findings have implications for developing evidence-based planning, design, and policy strategies to create livable streets and prevent street crime by planting more trees in walking-friendly environments.