DNA testing has become the gold standard for determining the paternity of a child – it definitively answers the question of who is the child’s father? DNA testing can establish paternity with a level of accuracy and reliability never before possible.
In the past, the establishment of paternity was based on largely circumstantial evidence, personal testimony, and tests of blood types. These approaches have many shortcomings.
First, personal testimony can be flawed, as a person’s judgment can be clouded by time, circumstances, or emotional issues. Second, whereas blood type can be used to rule out paternity in many cases – when the child’s blood type and that of the father are inconsistent with one another – positive verification of paternity can never be established using blood type alone. At least 5% and perhaps as much as 50% of all men will have a blood type that is consistent with paternity of any given child. By contrast, DNA testing can rule out 99.9999% of individuals – in some cases, even more – making DNA testing for paternity extremely accurate and trustworthy.
DNA paternity testing has many purposes. Here are the top five reasons that people may want to use a paternity test:
1)    Personal. Having a child is deeply personal. For a man, knowing whether or not he is the father has potentially lifelong consequences. It can mean the difference between having a lifetime relationship and commitment to a child, or no relationship. For the mother, knowing the baby’s father can deeply influence the rest of her life as well, affecting relationships, marriage, finances, and basic well-being. Not knowing the identity of the father can lead to confusion, turmoil, and conflict. Paternity testing can be done quickly, locally, and with a minimum of inconvenience.
2)    To establish legal parenthood. In some states, when a couple is unmarried, the law requires a paternity test to establish paternity before a father can be listed on a child’s birth certificate as the father. This may have many implications, as establishing parenthood can affect child custody determinations and legal support obligations, as well as custody and visitation rights.
3)    To obtain custody. A father who wishes to have custody rights for his child may be asked by the court to establish paternity through DNA testing. Similarly, the court may request a DNA paternity test when a mother believes a man is not the father of her child, and she does not want to share custody. DNA paternity testing will clearly establish whether the man is indeed the child’s father.
4)    To obtain child support. A mother may want to make certain that the biological father provides child support. A man who is thought to be the father may voluntarily undergo paternity testing or may be ordered by a court of law to undergo such testing. Child support determinations may depend entirely on clear results from a DNA paternity test when no other formal evidence is available and it is otherwise a matter of one person’s story against another.
5)    Immigration. A child born outside of the United States to an American father and a foreign national mother is usually eligible for American citizenship, with a few restrictions. The father may apply for citizenship through a consulate or embassy abroad by requesting the creation of a Consular Report of Birth Abroad (CRBA) – usually through a local U.S. embassy or consulate in the foreign country – which provides evidence of the birth and the child’s relationship to citizens of the United States. During the process of evaluating the CRBA and the evidence of parentage, the consulate or U.S. Citizenship and Immigration Services (USCIS) may determine there is insufficient evidence of parentage and therefore may request a DNA test that can unambiguously establish the blood relationship of parent and child. Samples can be collected overseas at U.S. embassies or consulates or other legally designated collection sites and transmitted securely to DNA testing facilities in the United States. Results are transmitted to the appropriate parties, including the USCIS, embassies, and attorneys.