One point of that after make to kill prisoners this penalty, parents of criminals suffer mentally distressful while hardly do the people who give decision might feel serenity in their soul. That is the activity of killing people is conducive to extremely pain in human's soul, they may be wrath and revenge to come back make serious crimes again and again.
Prisoners must be killed to prevent them from murdering again, either in prison, or in society if they should get out. Many people don’t worry to they come back to attack again. the death penalty this policy is conducive to social security.
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