Why didn't he just drop the knife and comply?
The rank and file idiot on the street thinks hollyweird solutions actually work like shooting to wound, sneaking up from behind or one mighty blow of the fist knocking someone unconscious.
When you are a cop going to work, nothing guarantees you will be coming home tonight. They live with that each day.
Not to mention the Police could just get sick of the delusional public and get a job at Walgreens for the same pay.