Heck I can see rubber rounds being useful for a situation like this, maybe carry 2 weapons one with rubber rounds and the other lethal depending on the situation. I don't know how well rubber would work so I'm just throwing it out there.
That comes with its own set of complications. I seem to remember an incident in New York where an officer meant to use his taser on a suspect, but he unfortunately grabbed his handgun and shot the person instead.
Cops also aren't trained to "shoot to kill". They are trained to stop the threat. If it takes one shot then it takes one. If it takes two then it takes two, etc. Trying to shoot at
anything other than Center of Mass while your body is dumping adrenaline would be damn near impossible.