The police killing of two black men — Alton Sterling in Baton Rouge, Louisiana, and Philando Castile in Falcon Heights, a suburb of St Paul, Minneapolis — last week horrified people around the world and brought protesters into the streets in large numbers across the country to proclaim that Black Lives Matter.

Yet just as quickly, in Dallas, a man who shot and killed police officers as Black Lives Matter supporters were demonstrating — killing five officers and wounding several more before being killed himself by police — provided the means for the media and law enforcement to shift the spotlight away from the epidemic of police violence and blame those who have risen up to protest.

Micah Xavier Johnson, an African-American veteran, opened fire on police during a Black Lives Matter demonstration in Dallas on July 7. There was zero evidence, even in the immediate confusion surrounding the attack, that Johnson was connected to the protest.