One of the issues that has come to the fore front in family law is paternity fraud.  Paternity fraud is generally described as using fraudulent methods to convince a man that he has fathereda a child. It can have lasting consequences since many states refuse to allow that father to later disclaim paternity when he find out he may not be the father of the child.  In the analysis by the courts, the basis for the belief is ignored and if the father has acted as a parent for a period of time, he is often precluded from disclaiming paternity based on a "best interests of the child" standard. the end result is  often the payment of child support for a child that is not his.   Statistics vary broadly on this issue. however, even the most conservative studies place paternity fraud at 1% and some place it as high as 30%.  The issue becomes even more murkly when the purported father is married to the mother and has no reason to suspect an affair.