Florida is about to revamp their paternity law. This article talks about the changes. As I understand it, if a man shows through DNA testing that he can not be the father of a particular child, even though he might be named on the birth certificate, he is no longer financially responsible for the child.
Makes sense to me. Why should a man have to pay support for child he didn’t father? The question you should ask yourself is “Why is this such a big deal? Why do they have to make this law? This should be common sense, right?”
Common sense isn’t all that common. Here’s more reading.