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Pieces of a whole: New Zealand operates as a representative democracy. This means ...

Sovereignty: from the Treaty of Waitangi to the United Nations: Who has supreme authority in ...

Sovereignty challenged: The idea of sovereignty is now very seriously weakened, according to ...

Te Tiriti o Waitangi: According to its preamble, the Treaty of Waitangi was signed in order to ...

How it all fits together: New Zealand is a democracy, meaning New Zealanders have ...

Representing the Queen: The Governor-General is the personal representative of our Head ...

Three branches of government: New Zealand's system of government follows the Westminster ...

Watchdogs for democracy: Former Prime Minister Sir Geoffrey Palmer has written that "Politicians provide news for ...

Association of former Members of Parliament



How it all fits together

The constitution
Constitution Act
Not quite laws
The Queen
The Executive
The Judiciary
Separation of Powers

New Zealand is a democracy, meaning New Zealanders have ultimate power over the way they are governed. But it is hard to make use of that power without knowing how the process of government works.

Of course, we get to vote for Parliament once every three years. But there is a lot more to democracy than elections. A democracy should give citizens many opportunities to participate in decision making, and provide:

  • checks and balances so that people with power cannot abuse it
  • respect for the voices of minorities, as well as those of the majority
  • independent and impartial judges who treat everyone equally
  • a free press
  • access to official information
  • protection for individual rights
  • freedom from corruption.

The constitution

In many nations (for example, the United States) the constitution is a supreme law that describes the nation’s major institutions, defines their powers, and sets out the rights of citizens. Parliament, government and judges must all do what the constitution says. The constitution can only be changed by special procedures (for example, a two-thirds vote by Parliament, or a referendum).

New Zealand’s constitution is to be found in a combination of:

  • formal legal documents (particularly the Constitution Act 1986, the Letters Patent Constituting the Office of the Governor-General, the Electoral Act 1993 and the New Zealand Bill of Rights Act 1990)

  • decisions of the courts (known as common law)
  • long-standing and recognised practices (some of which are described as constitutional conventions).

  • These are not 'supreme laws' and most of them may be changed by a simple Act of Parliament.

New Zealand’s constitution is based on the Westminster, or British, tradition. It has evolved over many years and has continued to change since we became independent of Britain.

Constitution Act

The Constitution Act 1986 is the formal statement of how our political system works. It describes the roles of:

  • the Head of State (the Governor-General representing the Queen)
  • the Legislature (Parliament)
  • the Executive (Cabinet)
  • the Judiciary (judges and courts).

Collectively, these form the core of our system of government. Each institution has a defined role to play. These roles overlap, but each also provides checks and balances on the others.

Not quite laws

Constitutional conventions are almost-but-not-quite laws. They are practices that have come to be recognised as effective ‘rules of the game’. Our formal laws often confer wide powers of discretion on those who implement them. In practice, however, these powers are limited by conventions. These conventions require that legal powers be used only in certain limited matters.

Conventions are not enforceable in the courts. If a convention is broken, the punishment is generally political, and rests with Parliament, public opinion and, ultimately, voters.

The advantage of conventions as opposed to laws is their flexibility. Formal laws can never allow for every possible circumstance that might occur. Conventions allow exceptions to be made, whereas laws do not.

The Queen

The Constitution Act says that Queen Elizabeth II is New Zealand’s head of state, and that the Governor-General is her appointed representative. Many legal powers are formally held by the Crown (in effect the Governor-General). Convention requires that these powers are used only on the advice of the ministers who form the executive branch of government.


Parliament is the only body that can make laws. However, Parliament delegates some lesser law-making powers. This enables government to make regulations about issues such as motor vehicle safety, and local authorities to make bylaws about rubbish collection, without having to go back to Parliament every time minor changes are needed.

A Bill passed by Parliament becomes law when signed by the Queen or the Governor-General. The Constitution Act also says that each Parliament may last for three years, unless it is dissolved earlier. The Governor-General has the formal power to summon Parliament after an election and to dissolve it for a new election.

However, by convention the Governor-General acts only on the advice of the Prime Minister. After each general election, Parliament must meet within about eight weeks.

The Executive

The Executive is the part of government that does the actual governing. It consists of all Ministers of the Crown (such as the Prime Minister and the Minister of Finance) and most public service ministries and departments (such as the Ministry of Education, and the Department of Labour).

Ministers of the Crown are responsible for deciding what policies the government should follow, the rest of the executive and the public service carry out those policies. Most important policy decisions are made by the Cabinet, which is made up of most Ministers of the Crown, and meets weekly.

The constitution says that only Members of Parliament may be appointed as Ministers of the Crown. By convention, the Prime Minister and other Ministers may only hold office as government while they are able to win a vote in the House on matters of confidence – issues that are vital to the government’s programme.

This also means that Ministers must be accountable to Parliament for the performance of the government. While elections are about choosing Members of Parliament, this convention links the choice of Parliament to our choice of government.

The Judiciary

The Judiciary is the referee which determines who is allowed to do what, should any disagreement arise. It holds the balance between the power of the state and the rights of citizens. The judges, who are the members of the Judiciary, have the power to stop the government from taking any action that goes against the laws made by Parliament, or the principles of common law, also part of our constitution.

To ensure their in-dependence, the Judges of the Court of Appeal and High Court are protected against removal from office and reduction in salary.

Separation of powers

Each branch of our government has different powers. In theory, each acts as a brake on the power of the others.

However, the development of political parties in the last 200 years has enabled Cabinet to effectively control Parliament, although the arrival of MMP has changed the nature of that control.

While the Governor-General theoretically has great powers, in most cases, convention requires that these powers be exercised on the advice of Ministers.

Nevertheless Parliament, govern-ment, the Judiciary, and even the Governor-General do not always agree. Judges sometimes rule that the government has broken the law. Parliamentarians are sometimes annoyed that judges don’t rule the way they would like. Ministers occasionally find that Parliament will not pass the laws that they ask for. These disagreements are not signs that something is wrong with the system: exactly the opposite, in fact. They are healthy signs that the balance is being kept. .



Photo shows three parliament buildings.

Parliament Buildings










Photo shows the Treaty of Waitangi in a framed case.

The Treaty of Waitangi is one of New Zealand's founding documents