Parentage tests determining the child’s parent may be needed for family law matters such as child support payments, custody, access, inheritance, and adoption. But with these concerns, more issues arise, including questions about processes and legal requirements.
Parentage DNA Proof
The law states that a person is the presumed biological father of the child if:
- the man was married to the child’s mother at the time she became pregnant;
- the man is named as the father on the birth certificate;
- the man signs a statutory declaration saying he is the father of the child;
- the man and the mother were in a de facto relationship at the time she became pregnant; or
- there is a court order saying the man is the child’s father.
These factors are considered “proof of parentage” in applications such as child support or maintenance.
If either the man or the woman believes the man is or is not the child’s father, even in cases of presumed proof of parentage, it is possible to request a court ordered DNA test to make sure. This report can be used to form the basis of a court order.
Parentage Order DNA Tests
Also known as paternity tests, this is DNA testing to establish whether there is a family (genetic) relationship, or lack of relationship, between individuals.
Samples of bodily fluids are taken (mouth swabs are increasingly replacing blood samples, though both are reported to be effective) from the mother, the assumed father, and the child.
Procedures
When paternity or maternity is questioned, the Family Court can require a court-ordered DNA test to establish biological relationships. This process involves a series of essential steps that both the mother and the alleged biological father must navigate.
- Application to the Family Court: The parties must submit court forms, including an application for a declaration of parentage and an affidavit, to the paternity test Family Court.
- Family court DNA paternity testing: The court has the authority to require a court ordered DNA test and can instruct accredited laboratories to provide samples for testing.
- Testing by accredited organisations: Legal DNA testing must be conducted by organisations accredited under the Family Law Act. These organisations will issue a report admissible in the Family Law Court.
- Utilising the report: The report generated from the legal paternity test may be used as evidence to assist in resolving various issues such as custody, access, and child support.
- Court’s consideration of refusal: While the court cannot physically force someone to undergo a parentage test, refusal to comply with a court ordered DNA test can be considered in the court’s decision. It is possible for a person to still be legally declared as the father despite their refusal.
Remember, seeking custody lawyer advice before initiating any court action and following the necessary procedures is always recommended.

Parentage Certainty
If the nominated father’s DNA does not match the child’s DNA, he cannot be the biological father and is excluded with 100% certainty.
If the nominated father’s DNA does match the child’s DNA, he is a possible father. The Family Law Court requires the report to determine a relative chance of parentage of at least 99.5%.
Parentage Test Participation
The mother, child, and assumed father should all be tested. If a sample cannot be obtained from the mother, the testing can still be performed though the results will be less conclusive compared to when both parents are tested.
Testing with just one parent is performed only in special circumstances.
Requirements
The Family Law Act requires:
- tests are conducted by laboratories holding an accreditation;
- samples must be collected in a controlled environment by a medical professional;
- a “line of custody” must be maintained for the samples; completion of Family Law Court forms and affidavit, signed by all parties and the medical professional witnessed by a Justice of the Peace on the day of sample collection;
- mandatory photo identification for all participants; and
- test results must be returned to the medical professional, who will pass on to those on the affidavit.
Photo identification is required in the event of a dispute about the test result. The photograph may be viewed to verify the identity of the person who gave the sample. (This may be at the discretion of laboratory staff unless accompanied by a court order).
The founder of the firm, Silvio is a Family Law Specialist Accredited by the Law Institute of Victoria, Accredited FindLaw Feature Writer in Family Law and is a Founding Member of the Collaborative Law Committee of the Law Institute of Victoria.