Paternity
Paternity, the state of being a father, can be legally established in several ways. When the parents of a child are married, paternity is commonly presumed. However, to determine whether a man is the father of a child born out of wedlock, a lawsuit known as a "paternity action" must be brought. In such a suit, paternity may be established if the alleged father admits paternity. If a man fails to participate in the process, then paternity may be fixed by default, or a judge may order that he provide a blood sample to compare blood types and, if necessary, DNA types with that of the mother and child.
Blood-group studies, which commonly employ the ABO system, cannot establish paternity but can conclusively exclude an alleged father from being a candidate. This is the case because a child must inherit his or her blood type (A, B, or O) from the mother or father; thus, if the child's blood type differs from both the mother's and the alleged father's types, the man could not possibly be a parent of the child. To conclusively establish paternity, DNA typing is required. Adequate samples for DNA typing can be collected from blood, semen, or body tissue such as the inside of the cheek. DNA typing compares strands of genetic material between the child and alleged father. While most courts in the United States require accuracy of 99 percent to establish paternity, comparing strands from various locations of the genetic material allows accuracy ratings of 99.9 percent. DNA typing allows an alleged father to be excluded with 100 percent certainty.
Upon the conclusion of a paternity action, the judge's order establishes paternity. Once paternity is determined, the court can consider the issues of custody, visitation, and child support. Paternity actions are also brought in cases involving family inheritances, insurance benefits, social security claims, immigration requests, and to establish the peace of mind associated with being able to determine whether the child may be at risk for any hereditary disease.