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How to Establish Legal Fatherhood (Paternity) in Wisconsin

Questions answered in this article:
What is paternity?   | How is paternity established in Wisconsin? | How long does a father have to establish paternity? | | How much is a paternity test?

Jump to a section:
Different Types of Fatherhood Under Wisconsin Law  | Paternity Testing in Wisconsin | Paternity for Unmarried Couples | What to Expect in a Paternity Court Case | Paternity & Child Support | The Role of a Guardian Ad Litem in a Paternity Case | Contesting Paternity

What is paternity?

Short answer: Paternity is the legal state of being someone’s father.

When a man acknowledges or establishes paternity of a child, he acquires legal rights and incurs legal obligations for the child. Some of these rights include the right to see the child and to make major decisions for the child. Some of these obligations include the obligation to pay child support and to provide (pay for) medical care for the child.

Different Types of Fatherhood Under Wisconsin Law

An acknowledged father is a man who agrees upon the child’s birth that the child is his and that he is the child’s natural (biological) parent. This usually happens when the man is married to the child’s mother and knows the child is his; or he is in a relationship with the mother and signs an acknowledgement in the hospital voluntarily agreeing the child is his.

An alleged father is a man who is alleged to be a child’s father by the child’s mother or by an interested third party (such as Child Support Enforcement), but who has not yet accepted responsibility for the child or who will only agree to accept responsibility for the child after genetic tests definitively prove he is the father.

A stepfather is a man who is married to a child’s mother but who is not the child’s biological or adoptive parent.

A presumed father is a man who, by law, is presumed to be a child’s father but who, in fact, may not be the biological father of a child. An example of a “presumptive” or “putative father” is any man who is married when his wife conceives a child. By law, the husband of a woman is automatically presumed to be the father of her child unless and until genetic testing proves otherwise or the husband, his wife, and the child’s biological father agree the husband is not the father.

An equitable father is usually a presumptive father who is willing to take responsibility for a child and who is willing to pay child support for a child that is not biologically his, but that he treats as his own. This might happen when a married woman conceives a child that is not her husband’s. If the wife does not tell the husband and the husband raises the child as his own and only later finds out he is not the biological father of the child, the husband might choose (or be court-ordered) to continue to act as if he is the child’s biological parent.

How is paternity established in Wisconsin?

There are three ways to establish paternity in Wisconsin:

  1. 1. Voluntary Acknowledgement of Paternity is when a man and woman jointly sight a voluntary form acknowledging that he is the father of her child without the need for a court order or genetic testing. Parents only need to sign this form if the mother is unmarried at the time of the child’s birth and there are no other possible fathers. Parents cannot sign a Voluntary Acknowledgement of Paternity if the mother is married at the time of the child’s birth—even if she agrees her husband is not the child’s father.
  2. 2. Adjudication is when a judge decides a man is a child’s legal father. This may happen when a man disputes that he is the father or disputes the validity of genetic tests tending to prove he is the child’s father. The judge can still declare the man to be the father if the evidence supports this finding and if it is in the child’s best interests.
  3. 3. Legitimation is when a mother and father get married after their child is born and sign an Acknowledgement of Marital Child form to establish paternity. This form gives the parents the same rights as if they had been married before their child was born.

Some people believe a Conclusive determination based on genetic test results is sufficient to establish paternity. But while genetic tests may prove a man is the biological father of a woman’s child, they do not establish paternity. Rather, genetic tests establish a legal basis for claiming paternity (if a man wants to parent the child) or denying paternity (if he has been alleged to be the father and does not want to parent the child).

How long does a father have to establish paternity?

Paternity can be determined any time, however, a court action to establish paternity must be commenced before the child’s 19th birthday. This means a man can only compel the child (or its mother) to cooperate with genetic testing or other paternity proceedings while the child is still a minor. Once the child is an adult, he or she can no longer be compelled by a court to participate in proceedings to determine his or her paternity.

Likewise, a child (or its mother) can only commence proceedings to establish paternity before a child turns 19. Once a child is an adult, a man alleged to be its father cannot be compelled to undergo genetic testing or participate in paternity proceedings.

Paternity for Unmarried Couples

If the mother and alleged or presumptive father cannot agree to sign a voluntary paternity acknowledgement, they must determine paternity through a Paternity Action in family court.
For the Mother: An unmarried mother can commence an action for paternity by alleging a man is the father of her child. The man will be notified of her paternity action. If he disagrees with her allegation, he can contest it. He can also request genetic tests to prove or disprove his paternity.

For the Father: If an unmarried man believes he is the father of a woman’s child and she denies it or refuses to acknowledge it, he can commence a paternity action. If the woman disagrees that he is the father, she can contest the action. Either party can request genetic tests to prove (or disprove) the child’s paternity.

Paternity Testing in Wisconsin

Paternity testing consists of a lab test that analyzes the DNA of a mother, an alleged father, and a child to determine the child’s parentage.

How much is a paternity test and how is it done?

The cost of genetic testing varies widely and depends on many factors (such as who is providing the testing, geographic location, local court rules, etc.).

Typically, the court will order one or both parties to pay for the genetic tests. If the parents are indigent, the county will often pay for the testing. Child support agencies often offer genetic testing at a reduced cost. Tests require the cooperation and participation of the mother, alleged father, and the child and usually consist of a swab taken from inside the mouth. It is safe for all parties involved—no blood or needles!

Sometimes parties seek a private test at a local lab or administer a home paternity test from a drugstore. If the parties later wish to admit the results of these tests as evidence in court, it will be up to the judge to determine whether the test results are accurate, reliable, and legitimate. If the judge has any concerns about the veracity of a private test, they can order the parties to take another test administered by the court via the child support enforcement agency.

If a man submits to court-ordered genetic tests that determine he is NOT the child’s father, he will not be ordered to pay for those tests.

Can you get a paternity test while pregnant?

Prenatal paternity tests cannot be administered by the child support enforcement agency or via home test kits. They can only be taken by an OB-GYN and must be approved and ordered by a doctor. Courts generally will not order prenatal paternity testing and will not order doctors to conduct such tests.

Paternity actions require the baby to be born alive before a court will order testing or make other orders relevant to the child.

Can I refuse a court ordered paternity test?

No. If you are ordered by a court to submit to a paternity test, you must comply with the order. If you do not, you can be held in contempt of court and can be fined, jailed, or both.

Can a mother refuse a paternity test?

If an alleged father asks a mother to submit to genetic testing, she can refuse. However, if a court orders her to submit to genetic testing, she must comply with the order. Her failure to do so can result in her being fined, jailed, or both.

What to Expect in a Paternity Court Case

After a child is born, either the mother, the father, the child, or the county child support enforcement agency will file a paternity action in the county’s family court.

  1. 1. Child support enforcement typically files the action when the mother or the child receive public assistance benefits.
  2. 2. If the mother knows who the father is, the action will allege that he is the child’s father. He will receive copies of the court action and will be summoned to appear in court to either admit or deny paternity of the child.
  3. 3. If the mother is not certain who the father is and there is more than one possible father, all possible fathers will be notified of the proceedings.
  4. 4. When the possible father appears in court, he can either admit he is the father, deny he is the father, or request genetic testing to determine whether he is the father or not.
  5. 5. If he admits he is the father, the case will proceed to a “terms” hearing and the court will establish orders regarding custody, placement, child support and such other matters as how the parents will provide and pay for health insurance for the child or claim him as a dependent exemption on their tax returns.
  6. 6. If an alleged father denies he is the child’s father, the court will usually take evidence to establish why he does not believe he can be the father of the child. The court will also usually order genetic tests to see if the man can be excluded as the child’s father.
  7. 7. If the genetic tests prove the man cannot be the father of the child, he is dismissed from the paternity action and the court will question the mother as to who else might possibly be the father of her child.
  8. 8. If the tests prove the man is the father of the child, the action will then proceed to a terms hearing where court orders relevant to the child’s care and support will be made.
  9. 9. When genetic tests are ordered, the court will suspend making further orders until the results are received. It takes approximately two months for the court to receive genetic test results. If a man wants to challenge the results of a genetic test, he can request a jury trial on the issue of whether he is the legal father or not.
  10. 10. If either parent does not like the “terms” established by the court and wants to challenge or change the amount of child support, visitation, etc., that parent can seek a de novo review of the court’s terms.
  11. 11. The case will then proceed to a judge. Depending on the circumstance, the judge may or may not appoint a guardian ad litem to represent the child’s bests interests and to give the court a recommendation as to the “terms” most beneficial to the child.
  12. 12. A court can order a name-change for a child incidental to a paternity action. Once paternity is established, the court can either change the child’s last name to one agreed upon by both parents, or if the parents cannot agree, the court can give the child a hyphenated last name consisting of both parents’ legal surnames.

Paternity & Child Support

Both parents have a legal obligation to support their child.

Once paternity is established, the court will set a child support order based upon the amount of time the child spends with each parent and the amount of each parents’ gross incomes.

If the mother or the child receive public assistance benefits, child support enforcement will help the court establish a child support order and the mother may have to assign her child support benefits to the State of Wisconsin in reimbursement of public assistance received.

The Role of a Guardian Ad Litem in a Paternity Case

A guardian ad litem can be appointed for a child in a Paternity Case when his or her parents cannot agree on “terms” such as custody, placement, or child support. It will be up to the guardian ad litem to perform an investigation into the child’s best interests and to make a recommendation to the court as to what orders would be most beneficial to the child.

A guardian ad litem will also be appointed in paternity actions when either the father or the mother of the child are minors. The guardian ad litem will then represent the minor parent’s best interests in the determination of paternity and the setting of terms.

Contesting Paternity

A man can contest a paternity allegation by denying paternity and then submitting to genetic tests that prove he is not the child’s father.

However, on rare occasions, a man can be adjudicated a child’s father even when genetic tests prove he is not the child’s biological father. This can happen when, for example, a man has acted as the child’s father, held himself out the world as the child’s father, and perhaps even believed himself to be the child’s father—only to later learn via genetic testing that he is not. Under such circumstances, a court may find it is in the child’s best interests to adjudicate the man to be the child’s father because it would be emotionally, psychologically, and financially detrimental to the child to NOT require the man to be the child’s legal father.

Can you sue for lying about paternity?

A court may void a judgment of paternity if fraud, duress, or mistake of fact is shown.

Talk to a Paternity Lawyer

To learn more about your paternity options, schedule a free consultation with an experienced family law lawyer at Karp & Iancu, S.C..

Related Content About Paternity In Wisconsin

Wisconsin Child Custody & Placement Laws – What you need to know about paternity rights as it relates to child custody and placement.

Child Support in Wisconsin – What you need to know about how to calculate child support.
Does a birth certificate establish paternity? – What you need to know about why a birth certificate doesn’t establish paternity under Wisconsin law?

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