Criminality spread: A "boomerang effect" of public transport improvements?

This paper aims to reveal the importance of public transport policies in the evolution of crime configuration and so, the vital responsibility of urban transports and criminality in social sprawl, entrepreneurial configuration and social structure on a city. Public transport policies have an essential role on criminal behavior and its evolution. Nevertheless, the relationship between accessibility or the degree of improvement of urban transports and criminality was underestimated and even almost forgotten. Adopting the hypothesis that the degree of transports improvements depends on the number enterprises on each zone, this study suggest that transport improvements degree impacts directly on the criminality rates of the city. Nevertheless, the magnitude of this impact depends on the observed type of the crime in a zone and on the concentration of that crime on other ones. This article developed a 2SLS model for each type of crime (5) in order to demonstrate the endogeneity and thus the causal relation of transport enhancements with respect to the criminal spread on the city of Bogotá. A spatial econometrics study is also done in order to show that the number and the kind of crime on each zone of the city may directly depend on criminality of other zones. Results suggest that, the number of some types of crimes on each zone depend directly on the level of improvements of publics transports and that an increase of accessibility reflected by a bigger presence of public transport improvements in a zone, may share out criminality to other zones of the city. Since there are more stations of Transmilenio, not only workers or students can travel more easily everywhere in the city but also offenders. Actually, after the enhancement of public transports, offenders may reach more easily zones and neighborhoods that they were unaccustomed to go. Negatives externalities like the better mobility of offenders and then, their possible choice to expand their criminal activity to new zones, can spoil positives effects of enhancements of public transports. Far from suggesting to not develop public transports or to isolate some ?dangerous? neighborhoods or inhabitants, this article shows that improvements of public transports may not only generate positive externalities. Policy makers should take in consideration the mutation and the shift of criminals in order to identify possible solution before the adoption of improvements of public transports on each zone and avoid that a ?boomerang effect? of improvements transports take place.