At the end of last month, 18-year-old Paul O'Neal was shot and killed by Chicago police in a South Shore backyard. Moments before, O'Neal had been in a car that had been reported stolen; he hit two police cars and fled before he was killed.

Why was he shot, and why did it happen so quickly?

Peter Moskos, a Baltimore cop with a Princeton undergrad degree turned criminologist with a Harvard PhD, spent nine hours cutting down the video released by IPRA into a coherent narrative (he also went on WBEZ to discuss it). And in doing so he laid out a scenario for how the pursuit of a stolen vehicle became "what is known, in technical police circles, as 'a complete clusterfuck.'"

The way he sees the events, there's one moment where everything goes wrong. One of the officers jumps out of his still-moving police car and shoots at O'Neal's car, which is passing between his car and another officer, who is standing on the other side of the street. First, he's shooting in the direction of his colleague. This, as Jeremy Gorner, David Heinzmann, and Dan Hinkel reported, is likely a procedural error. Police superintendent Eddie Johnson has said that there were "potential [procedural] violations."

That could include, as Moskos notes, shooting at a vehicle, which Johnson's predecessor Garry McCarthy prohibited in 2015 if "the vehicle is the only force used against the [officer] or another person." This is actually typical among big-city police departments; not universal, but not uncommon. The reasons are pretty obvious: police are shooting at a fast-moving target, and if they incapacitate the driver, there's nothing, for better or worse, to control the car.

Johnson immediately stripped two officers of their police powers. Moskos defends the second officer who fired at O'Neal's car, since he may have thought the shot fired in his direction by his colleague was coming from O'Neal or his passenger, which audio from the incident supports. Under CPD's use of force guidelines, cops can fire on a vehicle if it's not the only force used against them—e.g. if someone in the car is firing a gun. Nonetheless it appears that—barring further information—at least the first officer to fire may have violated police procedure.

Part of what makes Moskos's post so compelling is the plausible chain of events he describes. Because the first officer shoots, against police procedure, it could have given other officers concern that O'Neal was armed, even though he wasn't. So, Moskos speculates (there's not video of the fatal shooting itself) the police who caught up to O'Neal may have been acting with what turned out to be excessive force on the basis of their colleague's rash decision. All this, especially the officer firing in the direction of another, has Moskos beside himself. Second City Cop echoes Moskos's reaction, and finds another seemingly irresponsible action that "chilled us to the bone"—an officer who boosted another cop over a fence while holding a gun in his hand.

But Moskos goes a step further than pointing out a possible violation of police procedure: "You'll [i.e. the first officer to shoot] be criminally charged with something, as you should be. Probably convicted, too. And I hope you're fired for shooting at other cops."

This is bold, but there's reason to be skeptical. Moskos cites Tennessee v. Garner, the Supreme Court case that found it is unconstitutional under the Fourth Amendment to prevent a suspect from escaping unless "the officer has probable cause to believe that the suspect poses a significant threat of death or serious physical injury to the officer or others."

But Edward Garner, the man who was shot and killed in that case, was fleeing on foot and was shot in the back of the head. O'Neal was in a car. And very recent Supreme Court decisions have backed officers who shot unarmed suspects who were fleeing in a vehicle.

The first is the 2014 case Plumhoff v. Rickard. In 2004, Donald Rickard led cops on a high-speed chase through West Memphis, Arkansas, reaching speeds over 100 miles an hour through traffic and a rolling roadblock. They got him into a parking lot, in a tight spot but not quite cornered, where he hit a couple police cars. The suspect tried to drive away, and the police fired 15 shots; the car hit a building, and the combination of the gunfire and the crash killed Rickard and his passenger. (You can see the video here.) The officers were charged with reckless homicide, but the prosecutors "acknowledged the shooting… was justified because he was trying to run over the officers when they fired into the car." They were granted pre-trial diversion, and the charges were dropped. Rickard's daughter filed a lawsuit alleging excessive force, and the case went to the Supreme Court.

Samuel Alito delivered a short, definitive unanimous decision. The reasoning is extremely simple, and it begins with Scott v. Harris, a 2007 case about a car chase in which the officer ran the suspect off the road, causing a crash that rendered the suspect quadriplegic. In that case, Antonin Scalia addressed Tennessee v. Garner:

Garner did not establish a magical on/off switch that triggers rigid preconditions whenever an officer's actions constitute "deadly force." Garner was simply an application of the Fourth Amendment's "reasonableness" test, Graham, supra, at 388, to the use of a particular type of force in a particular situation. Garner held that it was unreasonable to kill a "young, slight, and unarmed" burglary suspect, 471 U. S., at 21, by shooting him ìin the back of the head" while he was running away on foot, id., at 4, and when the officer could not reasonably have believed that "[the suspect] . . . posed any threat," and "never attempted to justify his actions on any basis other than the need to prevent an escape," id., at 21.

Instead, the justices concluded that the car was itself a risk—but the way they addressed it opened up the door for Rickard (emphasis mine):

Although there is no obvious way to quantify the risks on either side, it is clear from the videotape that respondent posed an actual and imminent threat to the lives of any pedestrians who might have been present, to other civilian motorists, and to the officers involved in the chase. See Part III—A, supra. It is equally clear that Scott's actions posed a high likelihood of serious injury or death to respondent—though not the near certainty of death posed by, say, shooting a fleeing felon in the back of the head, see Garner, supra, at 4, or pulling alongside a fleeing motorist's car and shooting the motorist, cf. Vaughan v. Cox, 343 F. 3d 1323, 1326—1327 (CA11 2003).

Which is exactly what happened in Rickard. So back to that case:

We see no basis for reaching a different conclusion [than in Scott v. Harris] here. As we have explained supra, at ___, the chase in this case exceeded 100 miles per hour and lasted over five minutes. During that chase, Rickard passed more than two dozen other vehicles, several of which were forced to alter course. Rickard’s outrageously reckless driving posed a grave public safety risk. And while it is true that Rickard’s car eventually collided with a police car and came temporarily to a near standstill, that did not end the chase. Less than three seconds later, Rickard resumed maneuvering his car…. Under the circumstances at the moment when the shots were fired, all that a reasonable police officer could have concluded was that Rickard was intent on resuming his flight and that, if he was allowed to do so, he would once again pose a deadly threat for others on the road.

And that's basically the opinion in a nutshell. It was bolstered in the 2015 case Mullinex v. Luna, which was decided on an 8-1 vote.

That doesn't mean that what one or more of the cops did was right, or not in violation of CPD procedures; there are plenty of things you can do at any job that are technically legal but are also bad ideas that will get you disciplined or fired. And it's not the end of the story; there's still the matter of what happened in the backyard, where O'Neal was killed, which was not recorded.

Perhaps the law could evolve. Police departments are trying to limit high-speed chases, but right now the Supreme Court precedent is pretty clear. That alone doesn't eliminate the possibility that, as Moskos suggests, that criminal charges could be filed. But as Steve Bogira pointed out after another shooting—in which an officer shot 16 times into the wrong car, nearly killing one of its occupants, leading to IPRA's first recommendation that an officer be fired—criminal charges are incredibly rare. The case law surrounding deadly force and car chases would seem to make the possibility in this case rarer still.