I think your general attitude and approach is exactly, 180 degrees wrong, Jeff.
"A perfect example of why you should immediately comply with an officer's instructions." Yes, but you fail to mention that much more importantly, it's a perfect example of why cops should be trained correctly in deadly force; i.e. *IF* the guy with a gun is pointing said gun *AT* you, the officer, or raising it to do so, then by all means, shoot him down; but - on the other hand, if said guy with gun is *NOT* pointing said gun at you or raising it to do so, then it's not an imminent threat and no you can NOT shoot him. That's the all-important critical distinction.
Frankly, you sound just like the gun-ban crowd who try to pretend like it's impossible for the cops to ever tell the bad guy from the good guy, and thus CCW is a bad idea and will only get innocents killed. No, no, no - it's simply NOT hard to tell AT ALL, 99.99% of the time, this case being the outlier if you can even call it an outlier (it's really not even in this case). I guarantee you the (wrongful) shoot-ee was NOT pointing the gun at the cops. This is 100% pure and simple a negligent police chief who needs to take responsibility for very poor training -- for instilling the exactly-wrong attitude into his / her officers' training, to-wit: "anyone with a gun is always a bad guy" which is precisely what the notoriously anti-gun St. Louis city government and police force believe and train for.
"No amount of training is going to give the officers ESP so they can tell who the good guy is when they arrive on the scene."
Red herring / non-sequitor: You don't need a lick of ESP to tell that if a guy is NOT pointing a weapon at you, and is generally submissive and explanatory as opposed to aggressive or coy, you shouldn't and legally can't use deadly force, particularly absent any knowledge that this is your bad guy as described by the RP. All you need, actually is common sense and experience - common sense and experience that is, which is NOT constantly over-ridden by the gun-hating police chief and city government, by constantly training you to ignore your common sense and shoot anyone with a gun, even if your instinct tells you they're not a threat - due to the gun-hating politics which taint the training.
"I really don't know why so many people have such a hard time understanding this."
That's exactly what I say to the gun-haters who constantly assert that the cops can never tell who is the good guy so only more good people are going to get killed from CCW, when actual ya know, reality doesn't bear that out, and CCW has saved countless lives in incidents over and over and over again, and probably 999 times out of 1000, the cops can easily and nearly-instantly tell who is and isn't the bad guy from their experience and instinct (all of the circumstances combined, including, very importantly, how the other members of the publics' such as the RP's body language is toward the guy with a weapon) -- as long is this instinct isn't undermined by extraordinarily anti-gun training - the "shoot anyone with a gun no matter what" mentality that is pervasive among all blue lefty big city police forces, which means virtually all big cities in this country. The key criteria, other than body language and spoken word of the potential shoot-ee (of which there was plenty in this case) is whether the gun is being POINTED in your direction! If it's not, and if you have no other indication of aggressiveness or a specific description of the guy holding the gun as being the aggressor, as described to you by dispatch while en route, then it's simply not an imminent threat for which deadly force is justified.
"If you are involved in an armed confrontation it's best not to be visibly armed when the officers arrive and if you are, expect to be ordered to disarm and perhaps even cuffed until things are sorted out."
Absolutely, yes.
"Responding officers most often don't know what they are dealing with until they arrive and see for themselves."
True, but that doesn't mean that police chiefs and mayors don't have a strong ongoing positive duty and responsibility to strive to greatly increase communication with dispatch while en route, to specifically try to clarify who the RP is, and who might or might not be a good or bad actor, as well as a duty to train much much better. Any real, experienced, decent cop in America will tell you that in those circumstances, they would have been able to tell this dude wasn't a threat, and wouldn't have shot. In other words, one of the *reasons* they don't know what they're dealing with is gross negligence in not setting up a system where dispatch tries to pump more info from the RP, where dispatch is trained to give a lot more information en route, and above all, where the officers are properly trained to actually heed that information, mentally prepare before arriving, and make those all-important distinctions. Sometimes it's just inevitable that nothing more can be known about an incident other than basic facts, but I believe that very often, much more info can and should be given to the cops, and the cops specifically trained that a person having a gun does not, per se, mean they are the criminal, deserving of being shot. The focus has to be on the elements of proper deadly force use: (a) deadly threat, (b) imminent, (c) objectively reasonable fear and (d) actual subjective fear - ALL 4 of the boxes must be checked, not just some of them or "all but one" under the law. Here there were only two checked or at the most, three, if you believe that the fear was objectively reasonable - still no imminence if the gun ain't pointed your way or being swung up or around to do so. This is yet another failure of big city blue lefty police chiefs - not setting up a good dispatch system of rules, in addition to negligence in training. The training cannot consist solely of "do whatever it takes to come home at the end of the shift", which is what is actually is in most big cities around the country.
This is 100% about blue lefty anti-gun terribly-poor TRAINING.
In my o-PIN-ion.