So-called "zero tolerance" policing has been embraced as a way of reducing major crimes by focusing on minor ones. But there's another reason: fines and fees for low-level violations are now major sources of revenue for cities that have reduced taxation. When poor people can't pay, they're assessed with penalties — often increased until jails become debtors' prisons, especially for blacks and other minorities. That's led to anger, resentment and sometimes to violent confrontations with the police. We hear how back-door municipal finance causes social chaos.