Victoria Legal Aid

Proving who the other parent is

Information about the law when there is a disagreement about who is a biological parent of a child.

Sometimes there is disagreement as to who is a biological parent of the child. The law says that a person is the biological father of the child if the:

  • person is named as the father on the birth certificate or adoption certificate
  • person signs a statutory declaration (a legal document) saying he is the father
  • child was born during the marriage or period of living together
  • person lived with the mother at any time in the period between 44 weeks and 20 weeks before the birth of the child
  • court makes an order or finding that identifies a person as the father of the child.

Evidence of parentage

Parentage can also be proved or disproved with other evidence. This evidence is usually provided by DNA testing. DNA testing involves comparing a sample (usually a mouth swab) from each parent and from the children. Testing can be done voluntarily or ordered by a court.

Testing for legal purposes must be done by organisations accredited under the Family Law Act 1975 (Commonwealth). For a list of accredited laboratories see National Association of Testing Authorities (NATA) – DNA analysisExternal Link .

If the court orders a test and a person refuses to participate, the court may still make a decision based on the evidence it has before it. The person may be ‘declared’ (named) the biological father by the court.

It is important to get legal advice if there are disagreements about who is the other parent. If you delay applying, this could have serious consequences for your case.

More information

Child support agreements

Child support assessment

Child support payments

Family Tax Benefit and child support

Disagreeing with a child support decision

Adult child maintenance for over-18s

Childbirth expenses

Other support

Find out how you can get other support for parenting arrangements, child contact and child support.

Disclaimer: The material in this print-out relates to the law as it applies in the state of Victoria. It is intended as a general guide only. Readers should not act on the basis of any material in this print-out without getting legal advice about their own particular situations. Victoria Legal Aid disclaims any liability howsoever caused to any person in respect of any action taken in reliance on the contents of the publication.

We help Victorians with their legal problems and represent those who need it most. Find legal answers, chat with us online, or call us. You can speak to us in English or ask for an interpreter. You can also find more legal information at www.legalaid.vic.gov.au

Reviewed 12 April 2022

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