The media, news agencies, etc. are using the term "polygamy" because that's not in dispute, whereas "child-rape" will require some forensic DNA testing to prove, even though it's perfectly obvious it occurred.
Don't mince words. "Polygamy" is not the issue and everyone knows that. They just can't say "child rape" until it's proven forensically.
I stand strongly and firmly on the First Amendment, and defend the rights of any person to believe whatever they want to, and practice their religion as long as it doesn't involve illegal behavior. Thus I have no quarrel whatsoever with Mormons or anyone else on the basis of their beliefs.
It's only when the ACTIONS of a group, based on their beliefs, run afoul of the law, that I become exercised about it.
Since I doubt you're going to argue that child rape should be legal, and therefore be protected by the First Amendment's religion clause, I think we can agree that the actions taken against the FLDS sexual slavery prison are justified.
Sadly, I believe you are correct. The problem is that rape charges have to be proven individually in a court of law. While I have little doubt that rape occurred, I also doubt that every member in the sect was involved directly. Most probably knew of it but it would be very difficult to prosecute given the circumstances.