Dallas police chief David Brown, front, and Dallas mayor Mike Rawlings, rear, talk with the media during a news conference, Friday, July 8, 2016, in Dallas. Snipers opened fire on police officers in the heart of Dallas Thursday night, during protests over two recent fatal police shootings of black men. (AP Photo/Eric Gay)
An Army veteran was killed by Dallas police after the sniper slayings of five officers
READ MOREHundreds gather at the JJ Hill Montesorri School Thursday, July 7, 2016, in St. Paul, Minn. for a vigil following the shooting death by police of Philando Castile Wednesday night in Falcon Heights, Minn. after a traffic stop by St. Anthony police. (AP Photo/Jim Mone)
A Minnesota prosecutor he has asked for a "prompt and thorough investigation" following the fatal police shooting of Philando Castile
READ MOREIn this May 30, 2013 file photo, Texas state Sen. Juan "Chuy" Hinojosa looks at maps on display prior to a Senate Redistricting committee hearing in Austin, Texas. The U.S. Supreme Court handed Texas a victory Monday, April 4, 2016, upholding the state's system of drawing legislative voting districts based on everyone who lives there, not just registered voters. (AP Photo/Eric Gay, File)
Racial gerrymandering has resulted in underrepresentation of minorities in legislatures
READ MOREProtestors gather at the intersection of N. Foster and Fairfields, near the Triple S Food Mart after Alton Sterling was shot and killed by Baton Rouge Police in the early hours of Tuesday morning, July 5, 2016, in Baton Rouge, La. An autopsy shows Sterling, 37, of Baton Rouge, died Tuesday of multiple gunshot wounds to the chest and back, said East Baton Rouge Parish Coroner Dr. William Clark. Officers responded to the store about 12:35 a.m. Tuesday after an anonymous caller indicated a man selling music CDs and wearing a red shirt threatened him with a gun, said Cpl. L'Jean McKneely. (Hilary Scheinuk/The Advocate via AP)
Alton Sterling, 37, was shot and killed Tuesday by Baton Rouge police officers
READ MOREThe Republican convention in Cleveland is likely to be contentious
READ MOREComey says email handling was "extremely careless" but not criminal
READ MOREIn hard hit housing markets, financial firms buy up homes for rentals
READ MOREVIDEO: What Trump's recent staff changes mean for his campaign
READ MOREClinton's use of a private email server raised security issues
READ MOREThree girls and boy all under 5 are found dead; boy, 7, escaped
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