Section 17 of the Marriage Act (Chapter 280) lists the grounds. A void marriage is one that never existed in law, as distinct from a voidable one.
Section 17(1)
(a) either of the parties is, at the time of the marriage, lawfully married to some other person; or
(b) the parties are within the prohibited degrees of consanguinity or affinity; or
(c) the marriage is not a valid marriage under the law of the place where the marriage takes place, by reason of a failure to comply with that law’s requirements with respect to the form of solemnization; or
(d) the consent of either party is not a real consent because —
(i) it was obtained by duress or fraud; or
(ii) the party is mistaken as to the identity of the other party, or as to the nature of the ceremony performed; or
(iii) the party is mentally incapable of understanding the nature of the marriage contract; or
(e) either of the parties is not of marriageable age.
Paragraph (a) — an existing lawful marriage
Section 3(2) makes a customary marriage valid and effectual for all purposes. So a subsisting customary marriage engages paragraph (a) just as a statutory marriage does.
The same conduct is also bigamy under section 57.
Note the timing: the question is whether the earlier marriage subsisted at the time of the marriage. A marriage contracted the day after a decree absolute is valid; one contracted the day before is void.
Where the parties are already married to each other, paragraph (a) does not apply — see second ceremonies under section 71.
Paragraph (c) — the form required by the place of celebration
Paragraph (c) does not apply to —
(a) a marriage solemnized under the Marriage (Overseas) Act 1955 of Australia, including a marriage to which section 24 of that Act applies; or
(b) a marriage solemnized under Part V of the Marriage Act 1961 of Australia, including a marriage to which section 83 of that Act applies; or
(c) any other marriage recognized in Australia by virtue of either of those Acts or their regulations.
Paragraph (c) applies the ordinary private international law rule that the form of a marriage is governed by the law of the place of celebration. The exceptions in subsection (2) preserve marriages solemnised by Australian consular and overseas provisions, reflecting the close pre-Independence connection. See recognition of foreign marriages.
Paragraph (d) — no real consent
| Sub-paragraph | Vitiating factor | Typical situation |
|---|---|---|
| (i) | Duress | The party was forced — by threats, violence, confinement, or overwhelming family pressure |
| (i) | Fraud | Consent obtained by deception going to the marriage itself |
| (ii) | Mistake as to identity | The party married someone other than the person they believed |
| (ii) | Mistake as to the nature of the ceremony | The party did not understand that what was taking place was a marriage |
| (iii) | Mental incapacity | The party could not understand the nature of the marriage contract |
Where a woman is forced into a marriage, paragraph (d)(i) makes that marriage void. That is a stronger result than the section 5 remedies, because a void marriage never existed.
But note the limit: section 6(3) provides that Part III does not apply to customary marriages, and Part IV — which contains section 17 — is directed at marriages under the Act. For a forced customary marriage, the remedies are section 5 of the Marriage Act, section 86 of the Lukautim Pikinini Act 2015 where a child is involved, and a decree of nullity under the Matrimonial Causes Act.
Mistake in paragraph (d)(ii) is narrow. A mistake about the other party’s wealth, character, health or intentions is not a mistake as to identity, and does not make a marriage void.
Paragraph (e) — not of marriageable age
A marriage is void where either party is under the marriageable age — 18 for a male, 16 for a female — unless a Judge or Magistrate has made an order under section 7(3) authorising the marriage to that particular person.
Solemnising such a marriage is separately an offence under section 58. Where the party is under 18, section 86 of the Lukautim Pikinini Act 2015 makes facilitating the marriage an offence carrying five years.
The three qualifications on section 17
- Section 17(2) — the Australian marriages excepted from paragraph (c).
- Section 20 — a Judge may permit a marriage within the prohibited degrees of affinity, and the validity of the marriage is then unaffected.
- Section 21 — a Judge may permit a marriage within the prohibited degrees of consanguinity arising only from adoption, except where the relationship is parent and child or brother and sister.
On what a void marriage means for the children, see children of a void marriage; on the difference from a voidable marriage, see void and voidable compared.
Sources
- Marriage Act (Chapter 280) — ss 3, 6, 7, 17–24, 54, 57, 58, 71, Schedule 2
- Matrimonial Causes Act (Chapter 282) — s 35; Lukautim Pikinini Act 2015 — s 86
Before relying on anything here, read the current text of the Marriage Act (Chapter 280) and check for later amendments. If a decision matters to you, get advice — start with the Office of the Public Solicitor, or find a firm in the law firms directory.