Why do you think that sleeping with children is sexual abuse? Let's face it, there are probably middle aged fathers out there doing just that on occasions, when their children need reassurance, if they're ill for example - doesn't make them "abusers" does it?
Has Jackson slept with children other than his own? I think he mentioned in the interview with Martin Bashir that children had slept in the same room as him, but not in his bed. Jackson steadfastly maintains that he has been asexual in his relations with boys. A jury member said that "Things just didn't add up." with regard to the prosecution case.
Anyway, that's not what this organisation is defending, but rather this:
Now, you may spin this to include children in the 'whomever', but it is clear that it is young people they are defending against 'imposing abstinence, guilt and fear' about them 'wanting to have sex' and also the state attempting to 'enforce puritanical values pushed by religion, and provide a moral justification for government interference in all other aspects of life'.