TOPSHOT - A police officer patrols during a protest in support of the Black lives matter movement in New York on July 09, 2016. The gunman behind a sniper-style attack in Dallas was an Army veteran and loner driven to exact revenge on white officers after the recent deaths of two black men at the hands of police, authorities have said. Micah Johnson, 25, had no criminal history, Dallas police said in a statement. / AFP / KENA BETANCUR (Photo credit should read KENA BETANCUR/AFP/Getty Images)
