I am not sure if there is or isnt a reference in regards to this. However, castration IMO is a punishment that fits the crime. Unless someone tells me that it goes against the folds of Islam .....I still believe it's the way to go.
Thank you for this question, which reflects a deep insight and a true desire to get knowledge. I hope we all going to learn something out of it ..
When some body waves a green signal for castration , He/she is actually going against the basic teaching of Islam . Where Islam caters for the physical and the psychological fitness of prisoners.
In Islam, prisoners, like all other members of society, have their rights.
They should be treated with care and get the due educational and religious courses that help them improve psychologically and be good citizens after they get out of the prison.
While in prison, they are not to be tortured or the like. Earlier Ask99 mentioned a case happened in USA , where the chap was killed by fellow prisoners.
Neither I, as a human being nor Islam as a religion of peace supports such moronic behaviour.
Let us just focus on the main issue and deal with the Prohibitions in disciplining or dealing with prisoners
Mutilating. It is not permitted to punish a prisoner by cutting off any part of his body or breaking any of his bones.
The Prophet (peace and blessings be upon him) forbade mutilation of prisoners of war and said, "Do not mutilate." (Narrated by Muslim).
Now why am I against castration …. because of the humiliation involved and I am afraid it will further expose them to more physical and psychological illness
My dear , Islam advocates clemency not such barbaric punishments