New York used to have a higher crime rate, and now it has a lower one.
We have two battling diaries on how DeBlasio's choice for NYC Police commissioner, Bill Bratton, is a either highly successful innovator who brought down the crime rate through "Broken Window" policing, or the person who started stop and frisk, and was the progenitor of Ray Kelly.
The likely truth is that neither the tactics of Bratton or Kelly have a whole lot to do with the crime rate, they were falling nationwide through this period, so it was part of a country wide trend.
The most likely cause of this was decreasing levels of lead in the environment following its removal from paint and gasoline some 20 years before crime rates fell off, an initiative of President Richard Milhaus Nixon. (BTW, Kevin Drum was all over this at Mother Jones)
It entered our gasoline following the end of the 2nd World War (where it was actually quite militarily significant, we could run engines on 100-120 octane, while the Axis powers were using something around 90 octane), and started being cut back in the early 1970s. (It was banned in paint about this time.)
Yes, Nixon, the creator of OSHA and the EPA.
What this means is that question about Bratten, or Kelly, or stop and frisk is not about crime rates, but rather whether the techniques applied do more damage to our society, and I would argue that stop and frisk as a technique of ethnic intimidated is so thoroughly corrosive that it must be ended.