Given the results of projects like Project Innocence, that has released well over a hundred death row inmates with DNA testing, can anyone really be '100% guilty'? Also, castration is in most cases an irreversible procedure, much like the death penalty- so if they are later found to be innocent (or mentally unfit, etc.), there's no going back, the punishment has been done.
My problem with this is the fact is, what if someone is really innocent and wrongly accused? It happens a lot, at least from what I understand. It happened to a good friend of mine, wrongly accused because a kid didn't like him and he spent 5 years in jail. What if they would've castrated him?
I am against castration as I against corporal punishment. There are some truly evil people in this world I think by inflicting physical harm on them we are no better than they. Incarceration should be a deterent for most people, for those that it is not effective, they would probably continue to pursue their crimes regardless of the punishment however severe.
What would castration achieve? What are the benefits of performing it?