Related articles: $  BLOOD TESTING
$  DNA TYPING
$  GENETIC TESTING
$  HUMAN LEUKOCYTE ANTIGEN TEST

Various scientific means of proving or disproving paternity are covered in seperate articles.

1.  Sufficiency of Uncorroborated Admission

An uncorroborated admission of paternity has been held insufficient evidence to sustain a judgement.{footnote}In re Cheryl B. v. Alfred W.D., 99 Misc. 2d 1085, 1088, 418 N.Y.S.2d 271, 273 (Fam. Ct. 1979).{/footnote}

Presumption of Legitimacy

A child born to a married woman who is generally presumed to be legitimate. The presumption has been held not to apply where the husband and wife were not cohabitating at the time of conception.{footnote}Jackson v. Jackson, 67 Cal. 2d 245 (1967).{/footnote}  That the marriage in question could be declared invalid does not affect the presumption of legitimacy, however.{footnote}Ill. Rev. Stat. ch. 40, & 2505.{/footnote}

The presumption may only be rebutted by clear and convincing evidence.{footnote} [3124]CHECK Michael H. v. Gerald D., 491 U.S. 110 (1989).
McCue v. McCue, 604 A.2d 738, 741 (Pa. Super. Ct. 1992).
            But see Burston v. Dodson, 390 A.2d 216, 221 (Pa. Super. Ct. 1978) (holding that evidence that there was no opportunity for intercourse, offered to rebut presumption, must be "exceedingly strong" or "overwhelming").{/footnote}  It may be rebutted by proof that the husband is impotent{footnote} [3125]Michael H. v. Gerald D., 491 U.S. 110, 124 (1989).
Cal. § 621 (conclusive presumption where woman was living with her husband at the time of conception); Ill. Rev. Stat. ch. 40, & 2505 (presumption of legitimacy where child born or conceived during marriage, or where husband subsequently consents to being named natural father on child’s birth certificate); Jones v. Trojak, 634 A.2d 201, 206 (Pa. 1993).{/footnote} or that there was never an opportunity for intercourse.{footnote} [3126]Michael H. v. Gerald D., 491 U.S. 110, 124 (1989)
Jones v. Trojak, 634 A.2d 201, 206 (Pa. 1993).{/footnote}  A man is presumed to be capable of having children in the absence of contrary evidence.  See CHILDREN–Presumption of Ability to Have Children. 

In Pennsylvania, some courts have held that blood tests are admissible to rebut the presumption of legitimacy only where the presumption has already been rebutted with proof of impotence or lack of opportunity,{footnote} [3127]John M. v. Paula T., 571 A.2d 1380 (Pa. 1990); Scott v. Mershon, 576 A.2d 67 (Pa. Super. Ct. 1990); McCue v. McCue, 604 A.2d 738 (Pa. Super. Ct. 1992).
            Contra Jones v. Trojak, 634 A.2d 201, 206 (Pa. 1993);Parenti v. Parenti, 397 A.2d 1210 (Pa. Super. Ct. 1979); Nixon v. Nixon, 511 A.2d 847 (Pa. Super. Ct. 1986).

{/footnote} which is arguably inconsistent with the Uniform Act on Blood Tests to Determine Paternity.{footnote} [3128]Codified as 23 Pa. Cons. Stat. 5104 (1991), it provides:
                        (G) EFFECT ON PRESUMPTION OF LEGITIMACY.  The presumption of legitimacy of a child born during wedlock is overcome if the court finds that the conclusions of all the experts as disclosed by the evidence based upon the tests show that the husband is not the father of the child.
See Heather Faust, Challenging The Paternity of Children Born During Wedlock: An Analysis of Pennsylvania Law Regarding the Effects of the Doctrines of Presumption of Legitimacy and Paternity By Estoppel on the Admissibility of Blood Tests to
Determine Paternity, 100 Dickinson L. Rev. 963 (1996).
{/footnote}

Estoppel

Courts have also applied common law estoppel doctrine to prevent a husband from contesting legitimacy after having treated a child as his own.{footnote} [3129]McRae v. McRae, 341 A.2d 762 (N.H. 1975); Time v. Time, 59 Misc. 2d 912, 300 N.Y.S.2d 924 (1969); Jones v. Trojak, 634 A.2d 201, 206 (Pa. 1993).{/footnote}  In some states this doctrine has been codified in a statute.{footnote} [3130]23 Pa. Cons. Stat. 5102(B)(2) (1991); Smith v. Smith, 300 So.2d 205 (La. 1974); In re Montenegro, 528 A.2d 1381 (Pa. 1987); {/footnote}    The facts giving rise to estoppel must be proven by "clear, precise and unequivocal evidence."{footnote} [3131]Nixon v. Nixon, 511 A.2d 847, 849 n.4 (Pa. Super. Ct. 1986).{/footnote}

Estoppel precludes the admission of blood tests to refute paternity.{footnote} [3132]Jones v. Trojak, 634 A.2d 201, 206 (Pa. 1993).{/footnote}

Exhibiting Child

The authorities are divided as to whether a party to a paternity action may exhibit the child to the jury in order to show the degree of resemblance to the alleged father.{footnote}40 A.L.R. 97.{/footnote}  Most courts will allow this under some circumstances.  It is more likely to be allowed whether the child is old enough that his or her feature are more defined.{footnote}Berry v. Chaplin, 74 Cal. App. 2d 652 (1946).{/footnote}  Most courts allow a child to be exhibited to the trier of fact so that the child’s race can be compared to that of the alleged father.{footnote}32 A.L.R.3d 1303.{/footnote}