With crime rates of of control in New York's major cities during the early part of that 25 year period from 1987 to 2012, police departments and politicians sought solutions. Common Sense actually prevailed as law and order politicians targeted the offending populations. New York City found that the same guy who was jumping the turnstile in the subway, once apprehended for that minor violation was actually in possession of an illegal handgun used in a homicide earlier that week. So they started targeting career criminals at all levels. Gang units were created to specifically go after the increasing gang activity that was controlling certain neighborhoods where crime rates were highest. Rules were set to keep known criminals from residing in public housing projects. New York State built more and more prisons to house career criminals. AND, homicide and other crime rates started dropping!
These actions were consistent with the recommendations of the 1987 commission and were effective.