@ Dracula,
Just like you say "humans arent born racist, this and that" and that they learn to do those things because of society and their circunstances (perhaps economically).
However the same way the learn to hate or learn a faith, they ALSO are taught (and i am sure in almost 99% of the homes around the world they teach this) that KILLING someone is completely wrong and one of the worst things one can do. Despite knowing this, they let their emotions, lack of judgement, stupidity, etc etc etc, get in the way and take them to commit this atrocious act.
There is absolutely NO reason why a killer should not be punished by death. That is a "killer" and not a "mentally ill" person.
The difference betwen the two is that, for obvious reasons, a mentally Ill person sometimes cant really control what is going on with them, for example a person with severe OCD; they have this intrusive thoughts and they must do the rituals to feel better or for that matter the riturals become automatic compulsions. The person suffering from this disorder can start suffering from depression, anger and think his or her life is a living hell because of that "demon" doing shiet with their head.
So a person with such a condition, must be understood that might not be in their right state of mind because they cant even control their own thoughts that are driving them insane.
But for someone who purposedly killed people or whom did illegal drugs and was under the influence and killed people, it is still an act that deserves the most harsh punishment. If you take a life, your life is the only thing that can equal to what you have done.
And trust me, that bullcrap about "oh but i didnt know what i was doing cuz i had too much beer or drugs" well guess what, there is a reason why the drugs are illegal, you MADE the desicion to incurr in those activities and must take responsibility.
So basically for me the only real way to forgive these murderors is if mental ilness is 100% proven with very carefull observation and studies done to the offender.