In my opinion, no one should be convicted of capital punishment, because they still have a purpose after committing crimes. I believe everyone has a cause and who am I to say they have already fulfilled that purpose.
In the Bible, God used murderers. Exodus 2:11,12 says, “One day, after Moses had grown up, he went out to where his own people were and watched them at their hard labor. He saw an Egyptian beating a Hebrew, one of his own people. Glancing this way and that and seeing no one, he killed the Egyptian and hid him in the sand.” (NIV)