Two-person marriage, civil union and de facto relationships
Oceania
New Zealand
New Zealand keeps adult marriage, civil union and de facto status pairwise, yet expressly handles some concurrent partner claims in property and inheritance law.
Concept artwork
Additional guardians are possible, but parentage remains principally dyadic
Only one partner receives relationship-based entry
Statute expressly handles more than one qualifying surviving partner
Marriage and present recognition
Marriage and civil union are each between two people. Bigamy covers additional marriage and civil-union forms and carries a maximum sentence of seven years in the primary offence.
The Family Proceedings Act may functionally recognise an overseas union that was polygamous where the parties' domiciles permitted it. That limited recognition does not authorise forming a plural marriage in New Zealand.
Relationships, property and inheritance
A de facto relationship is expressly between two people. The Property (Relationships) Act nevertheless contains rules for a marriage or civil union overlapping with a de facto relationship, and for two contemporaneous de facto relationships. Claims remain allocated to the relevant pairwise relationships.
The Administration Act directly addresses an intestate person leaving several qualifying partners. This is meaningful functional recognition at death, not a prospective group status.
Children and guardianship
Assisted-reproduction parentage rules generally recognise a birth mother and one qualifying partner. There is no general pre-conception path for three or more legal parents.
The Care of Children Act offers a wider practical route: an eligible partner may become an additional guardian and a court may appoint a guardian alongside existing guardians. Several adults may hold guardianship even when they are not all legal parents.
Immigration and healthcare
Immigration instructions acknowledge polygamous relationships in limited circumstances but permit only one partner to be included through the relationship route. Other adults need independent eligibility.
A personal-care and welfare enduring power of attorney normally has one acting individual, with a successor and named people who must be consulted. Property powers may appoint several attorneys.
Present building blocks
These are pathways to investigate with lawyers and other local specialists. They do not add up automatically to group marriage.
- Multi-adult cohabitation without another marriage or civil-union form
- Coordinated contracting-out and property agreements with independent advice
- Co-ownership shares, exit rules, wills, trusts and beneficiary nominations
- Additional guardianship and parenting orders
- Written donor and parenting intentions within the statutory parentage limits
- One welfare attorney, a successor and a named consultation circle
Reform gaps
These are the places where present law does not match a chosen multi-adult family.
- No multi-person marriage, civil union or prospective relationship register
- Concurrent claims remain a set of pairwise property and succession rules
- No general multi-parent or multi-adult adoption pathway
- Only one partner receives relationship-based immigration entry
- Personal-care attorney authority remains centred on one acting person