The issue with this case was that it wasn't an anonomous sperm donation via sperm bank. It didn't go through the proper channels and once the one parent tried to go on welfare/disability etc., the gov't went after all sources of income possible. In this case, c/s.
Personally, I don't believe in cases of sperm donation that the "father" should be held liable for c/s for two reasons:
1. sperm donation was intended to be an anonomous act so that those that could not conceive naturally would have an alternative option. To cause the donator to pay c/s would be punative and would lead to my next point:
2. if donators could possibly held liable for c/s, men who may otherwise donate, now likely would not. This would dry up the pool and all but eliminate the option from persons who relied on sperm donators.
It would be one big step towards destroying the ability of couples, especially lesbian couples, possibility of having children.