If you want the real answer, it's probably more that the underfunded justice system didn't have space to hold him. When it comes right down to it, we deeply underfund our legal system which creates choke points that result in violent offenders being back on the street, while low level, non-violent offenders sit in cells for months waiting to have their case heard. Having a properly funded system that does its job efficiently costs money though, and we have acquired the American allergy to taxes, even when they objectively benefit our health and safety.