I can say with absolute certainty, No, because I already believe that if I was careful about it, I could get away with murder, and even if I was caught, could get off with the lightest punishments.

However, I also recognize the finality of death. Killing someone is putting an end to any and all potential for good that person has, which I see as a waste. I'd far rather attempt to work the problems that person has free, so they could do good. Of course, if this required beating them half to death, I could roll with that.
I also recognize that there are some people who are simply too much of a danger to society to allow to live, but I've never encountered any of these types of people personally, and I'm hardly about to just pass death sentence judgments on people I've only heard about on the news.

no, i hate to cause pain for those that haven't earned it

but if someone were to ever hurt my wife or my daughter i might do it even if i were to get caught and would not hesitate to do it if i couldn't get caught

No!
....except Hitler, or anyone in those rankings...
...so technically yes...

No