I apply some skills learned from analyzing software incidents and especially from studying with experts in safety-critical systems. Mainly, I attempt to counter my own hindsight bias and look hard for how I can imagine the officers behavior makes sense to them.
Boulder Police Officer Resigns After Confronting Black Man Picking Up Trash — Colorado Public Radio — 2019-05-17 cpr 
I come to these videos with the benefit of hindsight. The event is in the past. The article headline tells me the officer has already resigned. This colors how I see the footage because I already know how the story turns out. I know that the police are found to have overreacted.
In the footage of the officer who initiates this confrontation, I can't see anything except racial profiling. I'm looking from the officer's point of view, but in my own mind, there is no reason to stop this person nor ask questions.
How can I make the officer's choice to stop Atkinson make sense?
This neighborhood is almost entirely student housing. It was once a subdivision of single-family homes. The police bust up a lot of college parties around here regularly.
We're in a college town. There's an established bias throughout the community—the troublemakers are college-aged.
This is a very upscale address for the neighborhood. Maybe the officer sees it as a tempting target for a troublemaker.
Atkinson definitely looks like a college kid—his visible youth, the clothes, the headphones, the courier bag over his shoulder.
And of course there's an established bias all over the country that suspects black men of being troublemakers.
The officer claims a suspicion of trespassing. On that basis he exercises his authority to demand identification.
Colorado ACLU Know Your Rights: pdf
> Colorado is one of several states which have a “stop and identify” law. In Colorado, this law gives law enforcement officers the authority to require you to identify yourself if the officer reasonably suspects you are committing, have committed or are about to commit a crime
Atkinson immediately reveals his belief that the officer is abusing his power. He declines to identify the unit in which he lives.
It escalates badly from there. But ends abruptly as soon as a third party confirms he lives and works on the premises.
After all the escalation, the speed with which the event closes draws my attention. That looks to me like a glimpse into something about the protocol of the police department.
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Pete asked other questions.
I agree that his effort to deescalate was worthwhile, but I'm also struck by what a low standard we apply, in which his efforts seem praiseworthy. He could have done so much better. It's astonishing how little skill (training? inclination?) these officers seem to have in deescalation. There are so many things that any of them could have done to calm things down. My perception is that the thing that prevents it is their need to protect the ego of the officer who initially engaged (and ultimately resigned).
There is something going on here about saving face for the department. But I think it's deeper than just protecting ego.
We know, after the fact, from ideas implicit in the headline itself, this situation ends peacefully. The officers at the time cannot predict that future.
As I look again tonight, I also see senior officers teaching junior officers.
They are clearly positioned deliberately to surround him. The part you pointed out earlier "hey watch that crossfire" is part of surrounding and part of the training. I suspect this is a general-purpose tactic to contain suspects.
From the lens of looking for the on-the-job training, I see the senior officers standing back fair amount, letting the initial officer lead the encounter. There's no better teacher than experience. If this situation had been less dramatic it might have been a perfect training opportunity for the seniors to tell the juniors where things got a little too out of hand and how they could do that differently next time.
One of the officers in the background sneaks in at an opportune moment to pull the cleaning tools out of Atkinson's reach. A precaution, perhaps. Or maybe confirming that it really is only a bucket and aluminum grabber.
There was clearly active teaching and communications about the lines of crossfire. Even if the more experienced officers know this situation isn't life threatening, they still have habits and skills, and a role of teaching the juniors situational awareness in the small incidents that may save lives in bigger ones.
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I'll retreat now from my effort to find context and rationale for the behavior of the officers.
Atkinson is clearly justified in his sense of outrage. That situation was not acceptable.
The finale of my 4th degree blackbelt test was me facing eight unarmed martial artists. I've seen Sensei call for five or maybe six opponents, but never eight. Intimidating and also flattering.
Even there, my experience is nothing like Atkinson's. The eight who surrounded me were my friends. They did all actually come after me, and all at once, and they are trained martial artists, but definitely unarmed. No actual threat to my life—except by terrible accident.
Still, the felt experience of being surrounded by eight attackers was incredibly threatening in those moments before the attack ensued. Part of the test is the emotional experience of trying to find a calm center inside the fear—to reach for a felt sense of safety.
There is no way to be reasonable.
I feel memories of that fear when I put myself in the shoes of both Atkinson and the police officers. The officers were not under threat from this specific situation, but their awareness and collective posture, the details they're noticing reveal the fear for which they prepare.