What if you killed a sociopath and they ended up in hell?

Answer 1

By definition, a sociopath lacks a sense of moral responsibility. Those who lack a sense of moral responsibility automatically wind up in a hellish dimension after physical death. They have no choice. The non-living higher power on the Other Side known as The Light judges all regardless of belief system; this is confirmed by near-death experience and inter-life regression research. Regardless, I strongly suggest letting the police handle such matters and not doing said individual in on your own. With one rare exception: if you were to transition and were spiritually advanced enough to expand your consciousness into a Godhead in The Light. In which case, if you were to investigate - as people and events on the physical plane are much more obvious to those on the Other Side - and said individual is indeed confirmed beyond a shadow of doubt to be a sociopath, then, as a Judge in The Light you would only be serving "that which is good and true" by ousting his or her soul from corporeal life and letting The Light indirectly force him or her to reside in an appropriate hellish dimension. (A sociopath who happened to murder an innocent who expanded into a Godhead on the Other Side would not live for very long.) But for the vast majority who read this: best to just let the police handle crimes committed by a sociopath.

Answer 2

Well, if you killed a sociopath or anybody else, and died without repenting, then you will up in hell. You are unable to judge anyone else, judgment is God's alone, so you would have no idea with the person you killed went to hell or not; at least until you get there.