Paternity law, or father law, is the legal area dealing with establishing or disputing “paternity”, the legal relationship between a father and his child.
A child born to the wife during a marriage under common law is determined to be the husband’s child by a “presumption of paternity”. This presumption, can sometimes be rebutted by evidence to the contrary, generally prior to a formal court ruling involving divorce, annulment or legal separation.
In the case of unwed fathers, a man may come forward and accept the paternity of the child in what is called a “voluntary acknowledgment of paternity”, the mother or government can file a petition for a determination of paternity against a putative father, or paternity can be determined by the courts through estoppel over time.
Where paternity of the child is in question, a party may ask the court to determine paternity of one or several possible fathers (called putative fathers) based initially upon sworn statements and then upon testimony or other evidence.
A successful application to the court results in an order assigning paternity to a specific man, possibly including support responsibility and/or visitation rights.
In the United States, a divorcing father files a parenting plan with a district court which outlines how the parents will share responsibilities on matters such as custody, visitation, support and insurance.
Some paternity laws assign full parental responsibility to fathers even in cases of women lying about contraception, using deceit (such as oral sex followed by self artificial insemination (State of Louisiana v. Frisard) or statutory rape by a woman (Hermesmann v. Seyer).
If the context of inheritance rights, it will be the heirs of the deceased person who are attempting to dispute or establish paternity. In some states, DNA testing will be dispositive to establish paternity. In most states, however, there are a variety of rules and time restrictions that can deny inheritance rights to biological children of a deceased father.