Questions about paternity can be emotionally difficult and legally complex. Whether you are a mother, father, or another person seeking clarity, a paternity test can help establish the biological relationship between a child and a parent. In Australia, there are strict rules under the Family Law Act 1975 (Cth) (‘the Act’) about when and how a paternity test can be requested and used as evidence in family law matters.

This article explains how paternity testing works, who can request it, what the process involves, and how results affect parenting, child support, and other legal issues.

What is a paternity test?

A paternity test is a scientific DNA test that compares the genetic material of a child and an alleged father to determine whether there is a biological relationship.

In family law matters, only accredited tests are recognised as evidence. The accredited test can be completed voluntarily, or it may be court-ordered. Home or online tests are not legally valid, as they do not meet the strict chain-of-custody and identification requirements set by Australian law.

The test involves:

• taking a DNA sample (usually a cheek swab) from the child, the alleged father, and sometimes the mother;
• sending the samples to an accredited laboratory; and
• receiving a report showing whether the alleged father is the biological parent.

The accuracy of DNA paternity testing is generally very high.

When paternity becomes an issue in family law

Paternity can arise as an issue in a range of family law matters, including the following:

• Parenting disputes - where one party denies being a biological parent or questions another person’s parentage;
• Child support cases - where either party disputes responsibility for or entitlement to payments; and
• Birth certificate applications - where one parent seeks to add or remove a name.

The Federal Circuit and Family Court of Australia can make parentage testing orders when parentage is uncertain or disputed.

Presumptions of parentage under Australian law

Under the Act, there are legal presumptions of parentage. These presumptions include:

• if the person is married to the mother at the time of birth, they are presumed to be the father;
• if the person lived with the mother between 44 and 20 weeks before the child’s birth, they are presumed to be the father;
• if the person is named as the father on the birth certificate, they are presumed to be the father;
• if the court has previously made a declaration of parentage, it is presumed correct; and
• if the person has acknowledged paternity in writing, they may be presumed to be the father.

These presumptions can be challenged with DNA evidence. A paternity test result can either confirm or rebut these legal presumptions.

Who can request a paternity test?

A paternity test can be requested by:

• the court on its own initiative;
• the mother, if she wants to establish who the father is;
• the alleged father, if he doubts his biological relationship to the child; or
• an Independent Children’s Lawyer representing the child’s interests.

If both parents agree, they can arrange for testing privately through an accredited laboratory. However, if one party refuses, the other may need to apply to the court for a parentage testing order. The court will only make a parentage testing order if the parentage of the child is genuinely in dispute.

How to apply for a paternity test through the court

If there is disagreement about testing, an application can be made to the Federal Circuit and Family Court of Australia under section 69W of the Act.

The process generally involves:

1. Filing an application seeking a declaration or order for parentage testing;
2. Attending court, where the judge considers whether the request is reasonable and in the child’s best interests; and
3. If granted, the court issues an order directing the parties and the child to undergo DNA testing at an accredited facility.

If one party refuses to comply, the court can draw adverse inferences, meaning it may assume the results would have supported the other party’s case.

How the test results are used

Once testing is completed, the accredited laboratory provides a report. If the court accepts the test results, it can make a declaration of parentage, which becomes legally binding.

The results may be used to:

• confirm biological parentage;
• update or amend birth certificate information;
• determine eligibility or liability for child support; and
• guide decisions about parenting arrangements.

What happens if a paternity test is refused?

If a person refuses to take a court-ordered test, the court may:

• make findings based on the available evidence;
• assume that the person is the biological parent; or
• draw other conclusions depending on the circumstances.

Refusal can negatively affect the outcome of a parenting or child support case, particularly if there is no reasonable explanation for non-compliance.

Costs of accredited paternity testing

Court-ordered DNA tests must be carried out by laboratories accredited by the National Association of Testing Authorities (NATA).

Costs vary but typically range from $600 to $1,200, depending on how many people are tested and whether travel or collection fees apply.

In some cases, the court may order one party to pay all or part of the cost, especially if they initiated the request or have greater financial capacity.

Impact on child support and parental rights

Once paternity is established, several legal consequences follow:

• The father gains legal parental status and may seek decision-making responsibility for the child and/or for the child to spend time with him;
• The father may become liable for child support payments, assessed through Services Australia; and
• The child gains legal recognition for inheritance and family rights.

If paternity is disproven, the alleged father may seek to:

• have his name removed from the birth certificate;
• stop child support payments; or
• recover child support payments already made in some cases, though this can be complex.

Emotional and practical considerations

Paternity testing can have lasting emotional effects on parents and children. Before pursuing testing, it’s wise to consider:

• the potential impact on family relationships;
• how to discuss results with the child in an age-appropriate way; and
• whether counselling or mediation might help manage conflict.

Legal advice is recommended to understand both the process and its broader implications.

Get help from a family lawyer

Because paternity testing involves sensitive personal and legal issues, it’s important to seek advice from a family lawyer before applying to the court. A lawyer can:

• explain your rights and responsibilities under the Act;
• help resolve disputes without court proceedings;
• prepare the necessary court documents (if needed); and
• ensure any test results are used correctly in legal proceedings.