WriteNow: what would be a just consequence for a murderer?

A murder is a crime that can't be excused, for the person who commits murder there must be a severe punishment. However, it is important to point out that many times murder is committed by a person that is mentally ill, and there must be a different type of punishment for that. Solitary confinement for the person that murders and that is aware of there actions, only the basics, never see the light of day, no suicide options. Only basic food. For the mentally Ill I suggest the death penalty, there is no point in keeping them alive, one cannot be sure that they will repent and pay for there actions in solitary confinement. It would be better to just get rid of them.