Their argument is that road budgets are a consequence of the same poor designs that lead to conditions that promote crime as well. Busy streets tend to be safer

Their argument is that road budgets are a consequence of the same poor designs that lead to conditions that promote crime as well. Busy streets tend to be safer. Additionally, places that aren't economically self-sustaining drive people to property crime. All of this is addressed in the first pages of "The Death and Life of Great American Cities".