This question should never arise in a moral society. The whole point of paternity testing is to establish the identity of the father when there is doubt. The only reason that there can be doubt in such a question is that the mother is living an immoral life, having relations with a man or with men who are not her husband. That such testing should be commonly spoken of is the sign of the utter degradation of all public morality and the destruction of the family. The conception of a child only belongs to a marriage that is indissoluble, till death do they part. For it is the fruit of the mutual love and self-giving of husband and wife, which love is exclusive of any other person. Shame on any woman whose behavior is such as to cast doubt on who might be the father of her child.

Note that if husband and wife are equally bound to preserve the virtue of marital chastity, and fidelity to their marriage vows, it nevertheless behooves the wife to attach special attention to it. Her immorality by fornication before marriage or adultery afterwards is more opposed to nature than that of a husband, for she has a special duty to protect the family, upon which the raising of any child depends. Moreover, she is particularly evil and culpable if she has deliberately incited a man to lust after her, whether it be for money or vanity or any other material gain.

However, if this grossly immoral situation arises, it is then permissible to do paternity testing, to establish precisely who is the biological father of the child. The reason for this is that he has a duty in justice to support the child and also the mother during the time that she is taking care of the child, even though they are not married. He also has a duty in justice towards the child that he has conceived to ensure that the child receives nourishment, clothing, health care, emotional support and the instruction in the catechism and the divine truths upon which his eternal salvation depends. Since these grave obligations will last for many years and cost a lot of time and money, it is right that a certitude be first established concerning the paternity of the child.

There can also be other reasons for such DNA testing that are not of a moral concern, such as when a person wants to know about his racial origin, or health or genetic traits that might be tied to his ancestors.

Father Peter Scott .