Haha, yeah that's a good point xD.
Yeah, i believe in prison, if your comitted of a sexual crime against a child or female, then your better off dead, because if your going to prison for that, then the immates are for sure going to kill you >.>. In my book, serial murderers deserve to get locked away for life or worse; in this case the death penalty/capital punishment.
I think the thing about why rapists rape, and why killers/murder kill is because they have some sick fantasy in their minds, and they want to live it out with physcial contact. And of course, with murderers, it could easily be things such as: jealousy, anger, envy, lust, gain of power, authority, and so on and so forth. To me, I think if we do know these things, there could be a chance of lowering the rate of rape/murder, or even violence as a whole, but who's to say that other crimes won't begin to increase. Like let's take gang activity for example.
Let's say hypothetically, that we know the things that these rapists/murderers are thinking, and how exactly they expect to act out their desires. What would we really do with this information. As you know, humans are the greediest and most selfish species that existed, and we only want more of something, doesn't really matter of what, but we always want more "something". So say we do have this information, what exactly will happen to the people(citizens and victims)? How will this affect them? And what will become of them when/if this information is gathered/obtained?