In Philadelphia 45% of "Stop & Frisks" were unreasonable searches and seizures.

Although the number of pedestrians stopped by Philadelphia police under the city's controversial stop-and-frisk policy has dropped by 15 percent, an analysis by civil-rights groups shows that many stops are still made without "reasonable suspicion."

The American Civil Liberties Union and the law firm Kairys, Rudovsky, Messing & Feinberg filed a report in federal court Tuesday stating that the number of stops had decreased from 253,000 in 2009 to 215,000 in 2012 but that 45 percent of the stops were unreasonable searches and seizures.

A class-action lawsuit was filed in 2010 over stop-and-frisk, charging that minorities were targeted and that stops were often made without probable cause or reasonable suspicion. A settlement was reached in 2011, and the city agreed to procedural changes, including a review of training, distribution of information on investigatory stops and the creation of a database with stop reports.

Attorney Paul Messing said that although the report presented some good news, the bad news is "we have persistently high rates of bad stops." Reasons for stops included loitering and sitting on the steps of an abandoned property. Five percent of stops led to arrests, and less than 1 percent yielded guns or other weapons. Messing said that more changes to training and supervision might be needed and that if nothing changes soon, the court would be asked to impose sanctions.

The report also said that a two-month analysis of marijuana arrests in the city shows huge racial disparities. From September through November 2012, blacks made up 84 percent of marijuana arrests, and whites roughly 6 percent. Meanwhile, marijuana use is evidenced to be higher among whites than blacks. 
http://articles.philly.com/2013-03-20/news/37875813_1_stop-and-frisk-marijuana-arrests-unreasonable-searches-and-seizures

ACLU Philadelphia "Stop & Frisk" report:
http://www.aclupa.org/legal/legaldocket/baileyetalvcityofphiladelp.htm