I'm not currently a believer, but yes, without a doubt, yes.
Why? Because my God told me to do so. He had proven himself to be my God through mighty acts and had now asked me to be his right hand man in executing justice among the nations. Being brainwashed, I would gladly do whatever God said to do. I've been there, done that, in a sense as a JW.
Aren't JWs basically doing the same today, just without the bloodshed? Many that are converted out of their "worldly" religion to the JW faith can consider themselves as good as dead if they fall prey to the cult mentality. And the JW that converted him could easily be considered as one who took the life of that one. Because we all know from our time in as JWs, we had no life.