FILE - This undated file photo provided June 2, 2009 by the Chicago Police Department shows plainclothes Police Officer Alejandro "Alex" Valadez. Valadez, 27, was shot and killed early Monday, June 1,... more 
FILE - This undated file photo provided June 2, 2009 by the Chicago Police Department shows plainclothes Police Officer Alejandro "Alex" Valadez. Valadez, 27, was shot and killed early Monday, June 1, 2009, as he investigated reports of gunfire on the city's South Side. Opening statements began Tuesday, Sept. 20, 2011, in Chicago for Shawn Gaston, the first of three alleged gang members charged with first-degree murder in his death. (AP Photo/Chicago Police Department, File) less 
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Associated Press | Photo By Chicago Police Department, File
Tue, Sep 20, 2011 6:14 PM EDT