One night stand...fifteen years later...bill for child support?

this may seem like a harsh result but remember that the law’s number one priority here is protecting the rights of the child, not the rights of the mother or the father. The reason that there is a time limit on contesting paternity is that if you did not have that, then let’s say that that man contests paternity when the kid is 10 years old. Now the KID is the one who is out of luck.

It depends on the jurisdiction, actually. Here, for example, is Michigan’s statute:

http://www.legislature.mi.gov/(S(lrycwk45a4ua5p55o31nscrz))/mileg.aspx?page=getObject&objectName=mcl-722-717 (Emphasis added).