Why do they get off lightly?
It's a very general question with an answer that would take up many books to fill. In my mind, child molestation and rape (of any kind, not just child) are worse than murder. With murder, the person is gone on to the other side. Molestation, incest, rape, every day is fresh pain and suffering.
I have no doubt that many people that commit these crimes had similiar crimes done to them. Or they have mental issues. The recidivism rate of child sex offenders is insane. Many of these people choose to continue committing the most hideous crime imaginable. This is no way signifies that they should be absolved of guilt, rather that they are even more dangerous and scary than most run of the mill criminals.
This also balances with how intelligent and clever some of these sick individuals are. A popular trend amoung organized rings is to engage in "Satanic abuse". In other words, they wear costumes and dress up sex crimes in so-called Satanic ritual. When the kid testifies before the court, he or she sounds insane. Chemical castration is a joke. These freaks know that Depo-Provera chemical castration can be countered with regular testosterone. Testosterone is not a narcotic, and the Feds don't monitor it like they do narcotics. More than a few "specialized" docs are willing to write up a script for testosterone for enough cash.
These freaks are organized, and evil in a way many people cannot, literally cannot, understand. They don't wish to think other humans are capable of the evil that some commit. Read up on Franklin case to see an example of an extremely well connected network. A very well connected Republican politician named Larry King organized a child molestation ring that went rather high up into government. By blackmailing his clients, he bought a large amount of protection.
You can download the documentary at
http://www.vote.org/silence/ , be warned. While nothing graphic is shown or really meantioned in detail, some of the stories are enough to make one physical ill.
Marc Dutroux has been arrested and got life of murder, child abuse, child porn, as well as many other crimes. He ran a child porn ring in Europe, out of Belgium. He was convicted of murdering several of his victims. No one likely knows how many children he murdered or sold to be murdered. Many of his clients were the rich and powerful of Europe. His trial brought down a significant part of the Belgian government in resignations of many high ranking officials.
It's became apparent that Marc Dutroux is planning on spilling everything he knows about the European and American sides of his network. It will likely implicate a lot of well connected people, if he's not murdered or commits 'suicide' under suspicious circumstances.
http://en.wikipedia.org/wiki/Marc_DutrouxThe Franklin case, the Dutroux case and many others show that a number of politicians, judges and 'well connected' people commit child molestation themselves. They have no vested interest in making lengthy prison sentences for crimes they themselves commit.