In this Saturday, July 9, 2016 photo, Gillian Breidenbach looks out her window toward the area where Dallas police set up a command center to respond to the sniper attack that left five officers dead on Thursday night, in Dallas. The chaos and panic that ensued when Micah Johnson sprayed bullets at a protest against police brutality, killing five officers, resonated across a city increasingly defined by its diversity. Now Dallas has become a focal point in the nation’s ongoing debate and struggles around race and criminal justice. (AP Photo/Gerald Herbert) 

Democratic presidential candidate Hillary Clinton listens as Sen.Bernie Sanders, I-Vt. speaks during a rally in Portsmouth, N.H., Tuesday, July 12, 2016, where Sanders endorsed Clinton. (AP Photo/Andrew Harnik) 

Democratic presidential candidate Hillary Clinton addresses a gathering on the Boardwalk Wednesday, July 6, 2016, in Atlantic City, N.J. (AP Photo/Mel Evans) 

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) 

Hundreds 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) 

In 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) 

Protestors 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)