Oh, come on! You are recreating the picture to make it appear the Beaver Cleaver family and their little toy poodle Mitzi were the family in issue.
Actually, there was a late 30s man, a late 30s woman, a 17 year-old male, and a mixed mongrel mutt that looked like a pitt bull. There had been a reported felony in progress (wrong call, but cops are damned and sued if they don't treat every call as being based in fact). Meanwhile, cops are getting shot by bone-head "constitutionalists" merely for making traffic stops. This cop reacted in a way that could reasonably be expected given his vantage point.
It's unfortunate. It's a terrible shame the dog was killed. But hindsight helps no one but the nut cases and the John Edwards/Johnnie Cochran tort lawyer bar.