(Editor's note: This editorial was written before the news broke in Dallas Thursday night. The Editorial Board will be following that story as more details emerge Friday.)
The horrific video of Philando Castile, bleeding to death after being shot four times by police in the course of a traffic stop, is a searing, unforgettable reminder that black people in this country function daily with a level of risk most would find intolerable. The widespread grief and anger his death has sparked must be addressed quickly and vigorously, before even one more name is added to this tragic roll call.

A cafeteria supervisor at a St. Paul public school, Castile was the second black man to die at the hands of American police within 36 hours — horrifying by anyone's standards, but more so because his girlfriend sat beside him with her 4-year-old daughter in the back seat when a St. Anthony officer opened fire. According to his girlfriend, the shooting occurred after Castile told the officer that he had a permit to carry and had a weapon with him. That is not known independently because St. Anthony police have confirmed only the barest details. Same for Minnesota Public Safety Commissioner Mona Dohman, who would not even confirm the reason for the traffic stop in a Thursday news conference.

Accountability starts here. So far, we know little more than the version of events related in the stomach-churning video live-streamed by Castile's girlfriend as he lay slumped against her, dying. There is no reason why police, when one of their own is the shooter, should not be expected to give a quick, factual accounting of what's known so far even as the investigation continues.

Another troubling aspect of this case is the differing treatment accorded the officer who fired the killing shots and Diamond Reynolds, Castile's girlfriend. Following the shooting, the shaken officer was taken off to the side and comforted by colleagues. Reynolds said she was cuffed, put in a squad car with her terrified daughter, taken to the station and questioned by law enforcement before even learning Castile's fate. She was detained until 5 a.m., without charges. Contrast that with the officer, who presumably was allowed to go home and who was due to be interviewed by the Bureau of Criminal Apprehension sometime Thursday.

We may never know with perfect clarity what transpired on Wednesday night, and we have not yet heard the officer's version of events. We do know this is the latest in a string of incidents that have left hundreds of black men dead, creating deep divisions between the police and those they are paid to keep safe. That is simply intolerable and a sure path to civil unrest should it continue.

Gov. Mark Dayton, while acknowledging he did not have all of the evidence, went to the heart of the matter on Thursday: "Would this have happened if the passengers were white? I don't think it would have." That's why the U.S. Justice Department should heed Dayton's call to investigate the shooting. So far, department officials have said they will monitor and render assistance as needed. That is not enough. They are already investigating the shooting of Alton Sterling, the black man shot to death by police in Baton Rouge, La., on Tuesday. That level of independent investigation is needed just as badly here in Minnesota. The questioning and detention of Reynolds speaks loudly to the need for a civil rights investigation by the federal government.

Castile was, by those who knew him, counted as a good man — kind to the children he cared for at J.J. Hill Montessori school and valued by co-workers for his quiet compassion, warmth, intelligence and humor. But Castile and his background are not the issue here. The Rev. Brian Herron, at an emotional news conference on Thursday, said of Castile: "It really bothers me that we have to talk about how he was a good man, he didn't have a criminal record. I don't give a damn. He didn't deserve to die for a traffic stop. We're not animals."

It is difficult to call for calm in the community, to urge yet again that people work within the law and keep their protests peaceful. Patience has worn thin, and promises of change ring hollow in the ears of those who have heard them too many times over too many years.

Body cameras are good. More training is good. But what's most needed is accountability, from the highest levels of the criminal-justice system down to the lowest beat cop. There must be an unmistakable message that there is only one brand of justice in this country, and that every single citizen is entitled to its full measure.