Actually, the LEO was trained well enough. He gave forceful commands because that is what he was trained to do...problem was he didn't have the confidence to back them up. His mindset failed him, not his training.
You could tell he didn't want to have a confrontation, he desperately wanted the BG to comply. Too bad it wasn't up to him, the BG always dictates what level you have to take it to. You can't talk a nut job out of doing something crazy. Physical force needed to be the officer's plan A as soon as the guy approached him saying to "shoot him." He needed to finish it then and there, not just whack the guy a couple times and let him run back to the truck. By "finish" at this point I mean do what it takes to get him cuffed and under control, ASP/OC Taser, whatever.
When the BG got the gun, well, now you're in a gunfight whether you like it or not. Time to step up and be a gunfighter, "Get it out, get it on and get it over with." -What the instructor at the LE firearms instructor course always said, as opposed to asking him to put the gun down repeatedly until you get perforated.
If you carry a gun, then you are putting yourself in a position to be in gunfights. If you are in a position to be in gunfights, you better be a "gunfighter." When the lead starts flying, it doesn't matter that you are a nice person, that you never expected and don't want to hurt anyone, that you don't train enough or think of yourself as a "gunfighter" or tactical ninja. All that matters for the next 5-30 seconds is how well you run your gun and how firm your resolution is to win the gunfight. Emphasis is on the latter.
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NRA Instructor/Life Member
Certified Personal Trainer