In a number of discussions of the use of the robot-delivered bomb in Dallas to kill Micah Johnson, I've seen some folks say it was justified, because, in addition to the present risk posed by Johnson, "he had already killed 5 people." If this were part of the police calculation and not just online armchairing, then the police are not entitled to use that notion, as that is a fact to be established in a court of law. They are only allowed to assess present risk. The difference between those two sentences is the difference between a society of laws and a police state.
Nothing I'm saying here implies a yea or nay to the question whether the robot bomb was justified. There are specialists in risk assessment and ethical issues of law enforcement use of deadly force whose reports we can read and think about.
But the principle that the police must only consider present risk is what keeps us from condoning extra-judicial killings in which the police are judge, jury, and executioner. And insisting on that principle doesn't require special training; it's the very most basic duty of citizens to insist on it. It's what defines people as "citizens" in fact.
In addition, nothing I'm saying here implies that the USA is in fact "a society of laws," nor that there is a (non-color-marked) "we" who are "citizens." I'm purposely leaving open the possibility that in fact it has only ever been such a police state in a way that constituted whiteness as temporarily exempt from non-citizenship; I'm only making a conceptual distinction.
[UPDATE, following online discussion: 9:45pm, Sun 10 July: I think "reasonable suspicion he had killed 5 people" can be part of assessment of "present risk." I'm just objecting to the flatness of the statement of the armchair folks. (In this particular case, I'm not sure when the police shifted from the multiple sniper to the single shooter hypothesis, but even on the former, "reasonable suspicion the current shooter had been involved in an event with five deaths," can certainly be factored into the assessment of current state of mind of the shooter.}
Further, on the question of what to think about the threshold breached by the robot-delivered bomb in the Johnson case, we could consider the case of Christopher Dorner.
There were rumors of drones being used to track Dorner, and others being prepped for killing him, but they ended up using a bulldozer to knock down the walls of the cabin he was in and then using "burners" (flash-bang tear-gas grenades known to cause fires) which burned down the cabin, causing him to kill himself to avoid being burnt alive.
Pull quotes from this LA Times piece:
Samuel Walker, emeritus professor of criminal justice at the University of Nebraska Omaha, was critical of the decision to use the "burner" tear gas canisters. "It's true, he was firing at them. But he was cornered. He was trapped. At that point, there was no rush in the sense that he was barricaded. The standard rules on barricade situations are that you can wait the person out," Walker said. "To use a known incendiary device raises some very serious questions in my mind."
Other law enforcement experts interviewed by The Times, however, said the move was justified. Even though SWAT officers were certain to have known a fire was a strong possibility, the use of the gas was reasonable in the face of the deadly threat Dorner presented, they said. Allowing the standoff to carry on into the night, they emphasized, would have added an unpredictable element to the drama that officials were smart to avoid."