Story: Constitution

Unlike most countries’ constitutions, New Zealand’s is not contained in one document, but is made up a variety of laws, legal judgments and conventions. This means the country’s constitution can be changed comparatively easily, but that flexibility gives New Zealand’s Parliament more power than those in other Westminster systems.

Story by Matthew Palmer
Main image: Prime minister Helen Clark and MP Peter Dunne inspect New Zealand's constitution cupboard

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What is a constitution?

A constitution is the rules that set out how a country’s government can use its power. Most countries have a single document as their constitution. New Zealand considers itself to have an unwritten constitution because its constitution is made up of a variety of laws, court judgments, other government documents and conventions.

Constitutional conventions

Constitutional conventions are practices or behaviours that have been consistently followed. An example is the convention that all ministers publicly support cabinet decisions, whether they personally agree with them or not.

New Zealand’s constitution in the 21st century

The British monarch is New Zealand’s head of state, and is represented in New Zealand by the governor-general. The monarch and the governor-general act on the advice of government ministers.

New Zealand is a democracy, and must hold parliamentary elections every three years. A government must have the confidence of a majority of members of Parliament (MPs).

A few laws related to government are harder to change, but most only need the support of a majority of MPs.

The public service is directed by individual government ministers, who are directed by collective cabinet decisions. Together, ministers and the public service are the executive branch of government.

The judiciary (court judges) is independent of Parliament and the executive, and makes decisions on court cases. Judges cannot declare a law made by Parliament to be unconstitutional.

New Zealand belongs to international organisations such as the United Nations. International obligations require an act of Parliament before they can be enforced in a New Zealand court.

Constitutional change

Because New Zealand’s constitution is unwritten and made up of many parts, it is easy for some parts to change. This makes New Zealand’s constitution flexible, but means there is the potential for a government to abuse its power.

Constitutional relationships between the Crown and Māori

The place of the Treaty of Waitangi – signed by the British Crown and Māori chiefs in 1840 – in New Zealand’s constitution has been hotly debated. Since the 1980s there have been references to the treaty in New Zealand law, which has given it some legal effect.

Representative democracy and Parliament

New Zealand held its first parliamentary election in 1853. More and more people gained the right to vote over the rest of the century, with women winning the vote in 1893.

In the 20th century the biggest change to New Zealand’s constitution was the introduction of the mixed-member proportional (MMP) system of voting in 1996.

The power of executive government

The executive branch of government, led by government ministers, has a great deal of power in New Zealand. In the 1980s and 1990s some laws were passed that limited the power of the executive, most importantly the introduction of MMP. Other laws included:

  • the Official Information Act 1982, which means official information must be released to the public unless there is a good reason not to
  • the New Zealand Bill of Rights Act 1990, which means that the government can be taken to court over breaches of civil and political rights
  • the Human Rights Act 1993, which means people can make legal claims that legislation (law) was not consistent with the right to freedom from discrimination.
How to cite this page:

Matthew Palmer, 'Constitution', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/en/constitution (accessed 20 March 2024)

Story by Matthew Palmer, published 20 June 2012