Spatiotemporal Reorganization of Motor Vehicle Theft in Chicago After a Structural Break: Corridor Diffusion and Opportunity Structure Evidence

This study examines a pronounced shift in motor vehicle theft (MVT) in Chicago centered on August 2022 and asks whether the break coincided with spatial reorganization of urban opportunity structure. Two questions guide the analysis: whether MVT risk changed systematically across the break, and whether that change is consistent with a corridor-oriented opportunity mechanism linking target distribution, routine activity density, and escape convenience. Using grid-based incident locations, the analysis compares pre- and post-break clustering, hotspot configuration, and shifts in the spatial center of activity. Results show stronger post-break concentration and greater contiguity of high-risk areas, with intensified activity visually aligned with major transportation corridors and key nodes while the overall activity center remains near the inner-city core. Mechanism-oriented models relate incident counts to traffic accessibility, activity-opportunity density, and formal guardianship. Accessibility and opportunity measures show stronger and directionally consistent associations in the post-break period, whereas policing activity does not exhibit a robust relationship at the examined spatial scale and specification. Overall, the study advances a break-form-mechanism consistency framework for interpreting how abrupt contextual change can coincide with durable hotspot reconfiguration in an opportunity-driven, high-mobility offense.