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When is a Man a Father? Paternity in New Jersey


In New Jersey, a woman is considered the legal mother of a child if she gave birth to the child or if a she adopted the child. For a man, creating a legal parent-child relationship with a child (called “paternity”) can be a little more complicated.

Legally Established Paternity

Paternity can be legally proven in two ways:

  1. A court enters a Judgment of Paternity or Judgment of Adoption declaring the man to be the child’s father.
  2. If the man and the mother are not married, legal paternity is established (proven) if both parents sign a form called a Certificate of Parentage (COP) and file it with the state Registrar. A COP is a sworn statement that both parties believe him to be the biological father of the child. Parents may complete a COP before, or long after, the birth of the child. Hospitals in New Jersey offer unmarried parents the opportunity to sign a COP when they complete the birth certificate application, if it has not already been done. Once signed, a COP is enforceable proof of paternity and carries the same weight in court as a court-ordered judgment of paternity—even if the male is a minor when he signs it. A COP can be rescinded (canceled) within 60 days of the date of signing if a child support order has not already been entered.

Legal Presumption of Paternity

If paternity is not legally established, certain legal presumptions apply. A “legal presumption” is a fact that a court will assume to be true unless evidence admitted in court proves it untrue. For example, in criminal cases, the court presumes that the defendant is innocent until there is sufficient evidence to prove the defendant is guilty.

There are a number of situations that result in a presumption of paternity.

Parents who were married within 300 days of the child’s birth. The husband of the child’s mother at the time of birth is presumed to be the father of child. The law also presumes paternity for a man who was married to the mother but either divorced her or died within 300 days before the birth.

Couples who marry after the birth of the child. If a man marries the mother after the child is born, a legal presumption arises only if

  • He acknowledges the paternity in writing to the state Registrar,
  • He seeks to have his name added as the father on the child’s birth certificate,
  • He tells people that the child is his biological child, and
  • He agrees to or is court ordered to pay child support for the child.

Unmarried parents. A man not married to the mother is legally presumed to be the father of the child if he both tells people that he is the father of the child and he provides support for the child, before the child turns 18.

Husband who is not biological father. If a child is born during a marriage, but the biological father is not the husband, paternity will be presumed if

  • The biological father and the mother sign the COP;
  • The husband and the mother sign a form called a Denial of Parentage, acknowledging that the husband is not the biological father of the child; and
  • They file both forms with the state Registrar.

Artificial Insemination. New Jersey law provides a path for a married couple to be named the legal parents of a child created through artificial insemination if

  • The man and woman are married,
  • The husband consents to the procedure, and
  • The insemination takes place under the supervision of a licensed physician.

When a woman who is in a civil union or marriage with another woman gives birth by artificial insemination, her ­female partner or spouse is presumed to also be the legal parent of the child.

Warning about informal insemination and parental rights. Some women or couples have chosen to use donated sperm, either from a sperm bank or from someone they know, to become pregnant without medical supervision. In New Jersey, when a woman becomes pregnant from artificial insemination, the legal presumptions do not apply

  • If the mother is not married or in a civil union, or
  • If the insemination procedure is not supervised by a licensed physician.

In that case, the sperm donor, who is the biological father, is considered the legal father of the child, even if that is not what the donor or mother intended.

Challenging a Legal Presumption

When a man is legally presumed to be the father of a child, the mother, the child, or another man who believes himself to be the father may ask the court to decide paternity. Paternity challenges must take place before the child turns 23. The person challenging a legal presumption of paternity must present evidence that is “clear and convincing.” Clear and convincing is a legal standard of evidence that is higher than that required in most civil cases, but lower than the standard of evidence required in criminal cases.

DNA/Genetic Paternity Testing

In a contested paternity case, the court may order the child and other parties to submit to a DNA test. The results will determine the likelihood that the presumed father is, in fact, the biological father of the child. DNA paternity tests often result in greater than 95% certainty of paternity. Note that a home paternity test kit is generally not admissible evidence in court. A home test kit requires collection of samples (usually by swabbing the inside of the cheek) and mailing the samples to a lab. Court-ordered DNA testing requires the parties and the child to go to a lab to have the sample (swab) collected and tested.

In deciding whether to order DNA testing, a court will consider a number of factors:

  • The length of time between the proceeding to decide parentage and the time that the presumed or acknowledged father was placed on notice that he might not be the biological father;
  • The length of time during which the presumed or acknowledged father has assumed the role of father of the child;
  • The facts surrounding the presumed or acknowledged father’s discovery of his possible nonpaternity;
  • The nature of the relationship between the child and the presumed or acknowledged father;
  • The nature of the relationship between the child and any alleged father;
  • The age of the child;
  • The degree of physical, mental, and emotional harm that may result to the child if presumed or acknowledged paternity is successfully disproved;
  • The extent to which the passage of time reduces chances of establishing the paternity of another man and a child-support obligation in favor of the child;
  • The extent, if any, to which uncertainty of parentage exists in the child’s mind;
  • The child’s interest in knowing family and genetic background, including mental and emotional history; and
  • Other factors that may arise from the disruption of the father-child relationship between the child and the presumed or acknowledged father or the chance of harm to the child.

The parties should focus on these factors in either seeking DNA testing or asking the court to deny DNA testing.

No Legal Presumption

When there is no legal presumption of paternity, the legal standard to establish paternity is preponderance of the evidence. “Preponderance of the evidence” means that when all of the sworn testimony and items admitted into evidence are taken into consideration, a fact is more likely to be true than untrue. This is the typical civil court standard of evidence.​