Laws are supposed to be just, when they aren't they are at fault.
Laws are more about expediency than society scaled ethics. They're more 'atomic' if you will, more focused on the subject and those directly concerned by it rather than aiming at maximizing efficiency at a societal level.
A law obviously cannot encourage beating sex offenders up as its unlawful. But that's independant of the idea of "maximizing the good" (used that term for the sake of simplicity rather than actually believing in good vs bad, 'm a moral skeptic and such)
Expression of the post modern paradox : "For the love of god, religions are so full of shit"
Theory is always superseded by Fact...
... In theory.
“I’d hate to die twice. It’s so boring.” Richard Feynman's last recorded words
"Great is the human who has not lost his childlike heart." Mencius (Meng-Tse), 4th century BCE
Rationally speaking, i think they shouldn't be treated inhumanely despite their actions/offenses. It goes for any other criminal or convicted sex offender, they have the exact same rights as anyone else when it comes to how they should be treated. It's called Human Rights, and at the end of the day it applies to everyone no matter what they have done.
Violence towards insane people solves nothing. There is no thinking power devoted to analyzing the problem (the fact that some percentage of people are insane in this way).
The government's job should be to solve the problem; that's all. The short-term solution is to remove their ability to harm again (put them away). The long-term solution is to study the nature of the people with this sort of thinking. What else would actually help if the goal is to minimize the damage this kind of insanity causes?
The death penalty (or cruel treatment in prison) is really just a mechanism for revenge. Bad things happen to good people, so make bad things happen to bad people too! Unfortunately, this just means there are more bad things overall. Not to mention the fact that SOMEONE has to actually commit the act against the wrongdoer, making them a wrongdoer as well.
It seems to me that the pro-causing-pain-or-killing side really just wants to be able to get revenge on someone that hurts them. They just want the government to do it so it seems more objective or something.
I think everyone should minimize the damage they do. If bad shit happens, it's a sunk cost (as in, doing something after the fact can't change the fact). I think we can all agree that getting revenge (not for the sake of setting precedents) makes situations worse. So why do we allow it when the state does it? When prison workers don't stop it? When inmates do it to each other?
Solving violence with violence just seems so obviously inefficient.