Maybe it was Walter Scott’s fault. Maybe he did something to make Officer Michael Slager, of the North Charleston Police Department, in South Carolina, shoot him in the back. Maybe the fearsome Scott attacked Slager, nearly overpowering him and wrestling away his Taser, as Slager reported. Yet in Thursday’s newly released video, showing Scott undergoing a routine traffic stop for a broken taillight, there is nothing of that terrifying creature. Nor is he present in that other video, now imprinted on the national consciousness, showing Scott lumbering away, slower than his fifty years, with the Taser wires still trailing him as Slager all too calmly fires off eight rounds. We squint and look closer: Did the officer really drop his stun gun by the dying man’s body, fabricating a ready-made cover for murder?

Such mythmaking and forced recantation—the story of the dangerous black man who turns out not to have been dangerous—has become commonplace. Tamir Rice was a teen-age thug who reached into his waistband for a pistol, leaving Officer Timothy Loehmann no choice but to kill him. Then we saw the baby-faced twelve-year-old with the toy gun, and it became clear that Loehmann, previously deemed psychologically unfit to carry a weapon as a police officer, had shot the boy with no real warning, moments after arriving on the scene. John Crawford was allegedly threatening shoppers in a Walmart with a rifle and waving it aggressively toward Officer Sean Williams, who also had no choice but to kill him. Only the store video revealed that Crawford was holding an air rifle from the sporting-goods section and chatting on his cell phone when the police swept in. Only the video allowed us to see the man lay down his BB gun and try to crawl away.

We persuade ourselves that these black men must have done something to deserve being shot. Perfect victims, as advocacy lawyers know too well, are hard to find. Walter Scott owed back child support. He had had skirmishes with the law—one arrest, thirty years ago, for assault and battery, and a slew of others for nonviolent offenses, including failure to appear in court and to pay child support. But, if he wasn’t a delinquent father—if he didn’t steal cigarillos, as Michael Brown did, or sell loose cigarettes, as Eric Garner did—then surely he was guilty of something else. Stories that would beggar belief if the victim were a person we recognized—someone white, or at least wearing a tie—are tucked quickly away when the bleeding are not our kind of people. (Never mind that Scott was a veteran of the Coast Guard, like the officer who shot him.)

The law governing encounters like the one between Scott and Slager is so straightforward that it should be surprising that the Supreme Court took until 1985 to rule on it. In Tennessee v. Garner, the Court held that the use of deadly force to catch a fleeing suspect is an unconstitutional “seizure” unless that suspect poses a significant danger to others. The real question is why, death after death, beating after beating, as the major abuses and the minor humiliations pile up, we are collectively unable to face the fact that race makes too many police officers see threats where none exist, and makes the worst police officers, like Michael Slager, willing to deal death. The police beating, outside Detroit, of a fifty-seven-year-old black man named Floyd Dent made the news only after footage surfaced of an officer apparently planting an incriminating bag of cocaine. It takes a video to make the apparition disappear.

What do we imagine has changed in the past months and years? Has the behavior of some police officers suddenly worsened, or are smartphones—video sentinels in every pocket—finally confirming the laments of generations of black and brown Americans? If there had been no video of Walter Scott’s death, of John Crawford’s death, of Tamir Rice’s death, of Eric Garner’s death, how quickly would we have dismissed our doubts? Would we have taken seriously the evidence at hand and tried to determine what happened, or would we have allowed police and prosecutors to avoid the public accounting of a trial? How quickly we dismiss the stream of routine traffic stops, like Walter Scott’s broken taillight, that turn into summonses and warrants and arrests, lost jobs and lost freedoms, creating the volatile racial tinder that is ready for a spark. Did we listen to the people of Ferguson before the U.S. Justice Department released its scathing report, which revealed the town in Missouri where Michael Brown was killed to be like so many places across the nation, a town where poor and largely powerless communities are used as a source of municipal revenue?

The challenge now is to look past our default disbelief, to take seriously the complaints of those who we know are marginalized. We can no longer wait until there is footage to be shocked into outrage. Of course, there will be unclear cases and bad actors on both sides—suspects and police who lie to save their skins. But if we are to cease the particularly cruel disrespect of ignoring so many of our fellow-citizens, most often in our poorer neighborhoods of color, then we must act on what we know is true, on what they tell us is happening to them when we are not watching. Justice requires that we have the same seriousness of purpose when the cameras are off.