Many States apply the Lord Mansfield Rule, which bars the mother of the child and
her legal husband at the time the child was conceived or born from giving testimony
that might prove that the child is illegitimate, i.e., that the child is the natural
child of a man other than the husband.
If applicable State law does not permit introduction of such evidence, SSA will not
accept it for purposes of determining the child's status under State law. However,
the statements of the mother and her legal husband may furnish leads to other competent
evidence which SSA may use in rebutting the presumption of legitimacy.