When a married woman gives birth, the law presumes that her spouse is the baby’s parent (unless either of them can prove otherwise). But when an unmarried woman has a child, it’s important to determine who the father is, in a legal process usually known as establishing paternity or parentage. That’s because certain things can’t happen until a biological father has been declared the legal father of a child:
The specific rules and procedures for establishing parentage vary from state to state. But all states allow unmarried parents to establish paternity by signing a voluntary acknowledgment of paternity, either at the hospital when the baby is born or later. This declaration, when signed by both parents and submitted to the proper government agency, has the same legal effect as a court order establishing paternity.
If a man refuses to sign the paternity acknowledgment—but the mother claims he’s the father of her child—the state or the mother may start a legal paternity proceeding. Typically, this happens when the mother applies for child support or is receiving public assistance on the child’s behalf.
Mothers usually begin the process by applying through the local child support agency, but either parent may also file a petition directly with the court to establish paternity. (For instance, a father might do this in order to seek custody or visitation with the child.) Then, the mother, child, and the alleged father will generally have to submit to DNA testing. If an alleged father refuses to cooperate with a testing order, the court may automatically determine that he’s the legal father.