Through recordings and testimony, federal trial providing rare window into the NYPD

A federal civil rights trial is in New York is providing a window into the workings of the nation's largest police force, and the often unexplainable ways officers do their jobs.

The trial seeks to reform the practice of stop, question and frisk. New York officials hail it as a program that's deterred crime by taking weapons off of would-be killers and by making crooks reconsider carrying weapons.

But the trial exposes how the tactic creates messy and difficult encounters between police and the public.

The department has made about 5 million stops in the past decade, mostly younger black and Hispanic men. Only about 10 percent were arrested and few weapons are actually recovered, leaving many of those let go feeling angry and humiliated.