Everyone is so quick to try to assign cause to any phenomenon. I'm going to remind everyone that correlation is a necessary but not sufficient condition for causation, and there is often a significant time difference between the cause and the effect. I'm not saying that the stop and frisk tactics did or didn't work, but saying that stop and frisk wasn't the cause because stop and frisks were lower in this time period isn't valid. Maybe the increased stop and frisks in 2012 got the criminals off the street that were going to commit murders in 2013. Again, I'm not saying that stop and frisk is a good or legal idea, but the argument that some people are using to dismiss it is a flawed argument and needs some more work.