Given the information the cops were given, I'd be willing to give them something of a benefit of the doubt regarding the instantaneous assessment of whether the victim
1 acted in bemused/confused ignorance of his accused role in inadvertently selling himself as an imminent danger.
There were things that went wrong (and I'm put in mind of Boots Riley's tale,
here, except that he
knew there could be a misunderstanding) but the spoofed scenario set the armed police (who have to overwhelmingly be prepared for hot situations) up against an entirely unprepared individual (who had no reasonable idea about the hotness happening around him).
And consider asking police attending a
genuine potential murder/suicide scenario painstakingly explaining the entire situation to the potential murderer/suicidee to make sure they don't make any false moves whilst establishing the error.
Actual potential M/Ss (most of them!) would take the opportunity to finish the job (execute the hostages, light the splashed fuel, take pot shots at any cop or bystander within sight and turn their weapon upon themself if they still found it necessary) instead of being tactically surprised and prevented from carrying out most of their plan.
I have no idea how I'd react to suddenly being confronted at my front door. I have very low odds of being confronted by armed police (UK, not US, plus not being in a location or vocation where anybody would have reason to expect me to be armed and/or dangerous) but armed police will still (even here in the UK) have a much higher odds of encountering an armed offender within each and every situation that they, specifically, have been called in to deal with. It's an apparently asymetrical instance of game theory, but both skews of expectations
are true.
I blame the "service provider", for the SWATting, as prime offender. Coldly having created multiple instances of such a scenario with increasingly refined "triggering" in his spoofs, he was always going to cause more than mere inconvenience if he didn't get caught first. The person who "put out the contract" might possibly have never realised what he was asking for in hot blood, but still was actively complicit and thus covered in whatever the reverse is of glory. I reserve judgement on the intended-'victim' who gave the wrong personal information, though - they have a degree of guilt if they knew they were directing the others' malicious efforts to a real person, but an aimless/undelinerate defensive redirection of such retributions (perhaps suspected, if at all, to be nothing more than the old Fast Food Delivery Overload trick).
For the police shooter, the answer is no easier. To play safe, there should be Administrative Leave and full investigation of the circumstances (for everyone to learn from, even if there's no blame at the end of it) would seem the obvious first step. Depriving the forces of law and order of someone now
more experienced in handling these rare situations, at least temporarily, which doesn't immediately help evolve a better response team. One has to hope that the longer-term developments are worth the short-term purging.
1 Inarguably, regardless of who you consider the perpetrator(s)