Both. Imagine getting onto a fight with your boss and being killed the same day by the cop who responded to a call. It seems cops lives are worth more than citizens lives.
Well, it does tend to keep the rest of the employees in line. Night sticks are only used on employees asking for raises or showing up late.
All other things being equal, during performance of their duties, yes they are. Simply by virtue of the fact that they are constantly exposed to violent nutcases.
I have personally known 4 cops who were killed on duty.
I do not know any innocent civilians killed by a cop using questionable judgement. That tells me something.