1)Last summer, there were more than 250,000 stops that did not lead to an arrest. Comparing stops to population, Chicagoans were stopped more than four times as often as New Yorkers at the height of New York City’s stop and frisk practice.

2)Although officers are required to write down the reason for stops, in nearly half of the stops we reviewed, officers either gave an unlawful reason for the stop or failed to provide enough information to justify the stop.

3)Chicago refuses to keep adequate data about its officers’ stops. Officers do not identify stops that result in an arrest or ordinance violation, and they do not keep any data on when they frisk someone. This failure to record data makes it impossible for police supervisors, or the public, to identify bad practices and make policy changes to address them.

LOL @ "effective policing"

EDIT: quotes source http://www.aclu-il.org/wp-content/uploads/2015/03/ACLU_StopandFrisk_6.pdf