An Austrian dad has locked his daughter in a dungeon for 24 years. He raped her and produced seven children with her, one of whom died and was incinerated in an oven. The dungeon was soundproof and had a keyless entry system.
Many conservatives especially argue that parents have the rights and the privacy to take care of their children as they please. This is the argument behind homeschooling. Parents are also given privacy.
So you think that this Austrian dungeon case highlight how privacy and choice given to parents can be dangerous? In this case, one child attempted to escape and run away but the police caught her and returned her to her parents. They assumed that parents know what is best for their children. Austrian police did not want to let the children go to another family because they prefer the child to be with the biological father rather than an unrelated family. But this case clearly illustrates that a father doesn't necessarily care for his children.
The only solution to this problem then is more government intervention. E.g. regular checks to see if the children are okay, using sonar to find cavities in concrete, etc.
If this is not implemented and if the conservative idea that parents are made free to do as they wish to their children, then I believe this dungeon scenario will be replicated. The demand for child sex is strong. If there is a way to supply that demand that is safe and protected by privacy and freedom laws, it will be done. Right now there may be hundreds of children locked away in underground dungeons and we may not know.
This I would argue is a case for government intervention.