I saw that video. The cop is in the same class with the cop who shoots a motorist before he gets close enough to even see where the hands are, or shoots a woman in DC because she is fleeing with her kids in her car. The rule is don’t shoot a citizen unless there is the faintest shred of an excuse that can be claimed. Then shoot whom you will. It’s worse for dogs. For them no reason or excuse is needed other than it is a dog and visible.
The video I saw had the image of the boy blurred from a distance. Also the cop car was blocking the view. It is possible the cops mistook the boy with a toy for a man with a gun ... especially if the boy’s reaction to them appeared threatening.