I have seen the following arguments for the death penalty and against life imprisonment:
1) Emotional
This could involve anything from disgust at a gruesome murder or rape to revenge from the perspective from the victim or victim's family. I have lost respect for any kind of emotional response ever since I first heard the argument "Homosexuality is wrong because it disgusts me". I cannot see the difference between this argument and "Life imprisonment is wrong because criminals and their actions disgust me". If I find the the first unreasonable then it would be totally irrational of me to then accept the latter.
2) Economic
Such an argument... disturbs me. Firstly I believe it to be a sad reflection on human nature that money is even considered an issue when human life is under question. I find it equally disturbing when those against death penalty use it as their sole argument, effectively commodifying human life, as I do when it is used by pro-capital punishment types.
Secondly, it disturbs me because of the gross level of misinformation it demonstrates as it tumbles out of the mouths of those who are for the death penalty. Are they ignorant or is this a convenient way of pushing forward the death penalty because of their emotional responses (see number 1)?
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That is a brief overview. For more information on the economic issues go here:
http://www.tcask.org/press-releases/20040713%20press%20release%20-%20Tennessee%20Death%20Penalty%20Cost%20Study.html
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