A child born outside of marriage is not filiated to any man. A biological father can execute a formal acknowledgment under La. R.S. 9:392. That acknowledgment is enough to prove paternity, both in support and custody proceedings.1 Although old law provided that “signing the birth certificate” (or more likely being named on the birth certificate) constituted acknowledgment, this is no longer the case.2 A man can revoke the acknowledgment within 60 days of signing.3
If a man acknowledges a child born outside of marriage (with the mother’s consent) and marries the mother, a legal presumption of paternity is created and can only be undone by filing a disavowal action, not by mere revocation of the acknowledgment.4 Regardless of whether he marries the mother, a man may also bring an avowal action under La. C.C. art. 198 to establish his paternity of a child born outside of marriage.
A child, or more likely the child’s mother, can institute a paternity action to establish the paternity of a biological father.5 Other than in succession matters, this action may be brought at any time.6 This action is also available even if the child is presumed to be the child of another man.7
La. R.S. 40:34 adopts a paternity establishment procedure for child support purposes only. If a man is noticed and fails to contest the identification, or a blood test is done and he does not contest those results, there is a limited presumption of paternity created for child support purposes.8
If, as a result of a paternity action or a child support enforcement proceeding, a man is adjudicated to be the father of a child, but it is later determined that he is not, he can move under La. R.S. 9:399.1 to vacate the judgment. This petition must be served on the original parties and on DCFS if enforcement services are being provided.9 This must be brought within 2 years of the judgment of paternity or 2 years from when the adjudicated father should have known of the paternity action, whichever occurs first.10