The office was responding to a robbery and the fact that the resisting party ended up dead had nothing to do with his size. If he had simply followed the office’s orders, he would be alive and well today. Period!
If he actually believed that the kid had just robbed the store then he would have to know that he is dangerous and not to be engaged without back-up especially if he is 6-4 and 290.
It’s police SOP in departments across the country to call for backup.