New Zealand's government has three parts that share power. Parliament makes the laws, the executive runs the country, and the courts decide what the laws mean and whether they have been broken. Within the executive, the Prime Minister and Cabinet make day-to-day political decisions, while the Governor-General (representing the Sovereign) performs the formal and ceremonial functions that complete those decisions in law. The citizenship test checks whether you understand how these three parts work and how they keep an eye on each other.
What the test expects you to know
- The three branches of government and what each one does, recognised in the Constitution Act 1986.
- New Zealand has one Parliament chamber, the House of Representatives, with a baseline of 120 members of Parliament (MPs) elected for three-year terms under MMP. The actual total can be higher when overhang seats are added (the 54th Parliament has 123 MPs).
- The Sovereign (currently King Charles III) is the head of state, and the Governor-General is the Sovereign's representative in New Zealand.
- The Prime Minister leads Cabinet; Cabinet runs the day-to-day work of government and must keep the confidence of the House.
- A bill becomes law only after Parliament passes it and the Governor-General gives Royal Assent.
- Judges are independent of Parliament and the executive. This is the principle of judicial independence.
- The court hierarchy runs from the District Court up to the Supreme Court, which has been New Zealand's highest court since 2004.
- The branches check each other: Parliament holds ministers to account, the executive proposes most laws, and the courts can rule that government actions are unlawful.
The three branches of government
New Zealand follows a "separation of powers." This is the idea that the power to make law, the power to govern, and the power to judge should not all sit in the same hands. Each branch has its own job and its own way of being held to account, as the Ministry of Justice and the Courts of New Zealand both explain. Why this matters in a working democracy is the focus of democratic principles.
The three branches are:
- The legislature: Parliament. Makes the law.
- The executive: the Sovereign (acting through the Governor-General), the Prime Minister, and Cabinet. Runs the country and proposes most new laws.
- The judiciary: the courts. Interprets the law and decides disputes.
The Constitution Act 1986 is the main statute that sets out this structure, although it is not the only source of constitutional rules in New Zealand. Other rules come from older statutes, court decisions, and unwritten conventions.
Te Tiriti o Waitangi / The Treaty of Waitangi was signed on 6 February 1840 between the British Crown and Māori rangatira (chiefs). It is widely regarded as a foundational constitutional document of New Zealand. The Treaty is referenced in the Cabinet Manual, and a number of statutes incorporate Treaty principles.
Key facts:
- Three branches: legislature, executive, judiciary.
- Main statute: Constitution Act 1986.
- New Zealand has no single written constitution document. The rules sit across statutes, common law, and conventions.
- Te Tiriti o Waitangi / The Treaty of Waitangi (1840) is widely regarded as a foundational constitutional document.
Parliament: who makes the law
Parliament is where elected representatives debate and pass laws, approve taxes, and hold the government of the day to account. New Zealand's Parliament has just one chamber, the House of Representatives. There is no upper house. The Legislative Council was abolished in 1950 (taking effect from 1 January 1951).
The House has a baseline of 120 MPs, elected for a maximum three-year term using Mixed Member Proportional representation (MMP). Some MPs win electorate seats, and others come in from party lists. The actual total can be higher when overhang seats are added under the Electoral Act 1993; the 54th Parliament, for example, has 123 MPs.
Under section 14 of the Constitution Act 1986, Parliament has two parts: the Sovereign in right of New Zealand and the House of Representatives. In everyday speech, "Parliament" usually means the elected House.
Inside the House
The Speaker chairs debates and keeps order. The Clerk of the House manages procedure and paperwork. MPs sit on either the "front benches" (senior people, including ministers) or the "back benches," as Te Ara describes.
Key facts:
- One chamber: the House of Representatives.
- Baseline of 120 MPs (overhang seats can push the total higher; the 54th Parliament has 123), three-year maximum term, MMP electoral system.
- The Sovereign is technically part of Parliament for law-making purposes.
- The Speaker chairs the House.
The executive: who runs the country
The executive is the part of government that actually does things, like running schools, paying benefits, signing treaties, and sending police out. The Prime Minister and the rest of Cabinet lead it, and together they are sometimes called "the government of the day," to distinguish them from Parliament as a whole.
The Prime Minister and Cabinet
Cabinet is the group of senior ministers who make the big political decisions. It meets weekly. Cabinet is not directly named in the Constitution Act 1986. Instead, it operates by convention, with rules written down in the Cabinet Manual published by the Department of the Prime Minister and Cabinet (DPMC). Te Ara gives a useful plain-English overview.
Ministers must be MPs. They are appointed by the Governor-General on the Prime Minister's advice. They run government departments and answer questions in the House. If Cabinet loses the support, or "confidence," of the House, the government falls.
Key facts:
- Cabinet is led by the Prime Minister.
- Ministers are MPs appointed by the Governor-General on the PM's advice.
- The Cabinet Manual is the authoritative guide to how Cabinet operates.
- Cabinet must hold the "confidence" of the House to keep governing.
The Governor-General and the Sovereign
New Zealand is a constitutional monarchy. The head of state is the Sovereign, currently King Charles III. The Sovereign rarely visits, so day-to-day royal functions are carried out by the Governor-General, who represents the Sovereign in New Zealand. The current Governor-General is Dame Cindy Kiro; in September 2025 her term was extended to 31 March 2027 (from its original end date of 21 October 2026) to avoid a clash with the 2026 general election.
The Governor-General's job has three sides: constitutional, ceremonial, and community. The constitutional side is the most important for the test. According to the official role description, it includes:
- Giving Royal Assent to bills passed by Parliament. This is the step that turns a bill into law.
- Appointing the Prime Minister (by convention, the person who can command a majority in the House).
- Appointing and dismissing other ministers on the Prime Minister's advice.
- Chairing the Executive Council, which formally advises the Governor-General on the use of legal powers.
- Summoning and dissolving Parliament.
Almost always, the Governor-General acts on the advice of ministers. In rare situations they may use "reserve powers" without that advice, for example if no one can form a government after an election. These powers are used very sparingly. See voting rights & elections for how MMP normally produces the majority that determines who is appointed Prime Minister.
Key facts:
- Head of state: the Sovereign (King Charles III).
- The Governor-General represents the Sovereign in New Zealand.
- Royal Assent by the Governor-General is the final step that makes a bill law.
- The Governor-General almost always acts on ministerial advice.
- Reserve powers are rare backstop powers used without advice.
The judiciary: who decides what the law means
The courts decide what laws mean in real cases, settle disputes between people, and decide whether someone has broken the criminal law. Judges are independent of Parliament and the executive. This is called judicial independence and it is one of the most important checks in the system, as the Courts of New Zealand explain.
The court hierarchy
From the bottom up:
- District Court. The busiest level. Handles most criminal and civil cases. Set up under the District Court Act 2016.
- High Court. Handles serious cases and appeals from the District Court.
- Court of Appeal. Hears appeals from the High Court.
- Supreme Court. New Zealand's highest court. Hears final appeals on important matters.
The High Court, Court of Appeal, and Supreme Court are set up under the Senior Courts Act 2016. The Supreme Court was established in 2004 and replaced appeals to the Judicial Committee of the Privy Council in London.
There are also specialist courts and tribunals, such as the Māori Land Court, the Employment Court, and the Family Court. The Courts of New Zealand overview is a good place to read more.
Key facts:
- Court hierarchy: District Court, High Court, Court of Appeal, Supreme Court.
- Supreme Court is the highest court, established in 2004.
- Senior Courts Act 2016 covers the top three courts.
- District Court Act 2016 covers the District Court.
- Judges decide cases independently of Parliament and Cabinet.
How the branches check each other
The three branches do not work in isolation. They keep each other in line.
Parliament checks the executive. Ministers must answer questions in the House, defend their decisions, and keep majority support. If Parliament passes a vote of no confidence, the government must resign or call an election.
The executive interacts with Parliament. Most new bills come from the government, and ministers manage the parliamentary timetable. But the executive cannot make law on its own: Parliament has to pass it.
The courts check both. Judges can rule that a government action was unlawful or that a decision-maker did not follow proper process, and they interpret what Acts of Parliament actually mean when there is a dispute. The detail of the court system and your rights under it sits in criminal offences and the rule of law.
Parliament also has tools over the courts. It can change the law if it disagrees with how the courts have applied it, and it can set up new courts and tribunals. What Parliament cannot do is tell judges how to decide a specific case.
This balance is sometimes called "checks and balances." It is not written out neatly in one place. It comes from the Constitution Act 1986, older statutes, court decisions, and political conventions.
Common misconceptions
- Myth: New Zealand has a written constitution like the United States
- Reality: It does not. The rules of government sit across several statutes (including the Constitution Act 1986), court decisions, and conventions.
- Myth: The Governor-General has the same political power as a president
- Reality: Almost always, the Governor-General acts on the advice of elected ministers. The political power sits with the Prime Minister and Cabinet.
- Myth: Parliament and the government are the same thing
- Reality: Parliament is all the elected MPs (a baseline of 120, sometimes more with overhang seats). The government is the Prime Minister and ministers, who must keep majority support in Parliament but are a smaller group.
- Myth: The Supreme Court can strike down laws made by Parliament
- Reality: It can interpret Acts and rule government actions unlawful, but it cannot overturn a properly passed Act of Parliament. Parliamentary sovereignty still applies in New Zealand.
- Myth: There are two houses of Parliament, like in Australia or the United Kingdom
- Reality: New Zealand has one chamber, the House of Representatives. The upper house (the Legislative Council) was abolished in 1950, with effect from 1 January 1951.
Quick self-check
5 questions · not the official test
1. How many members of Parliament sit in the House of Representatives?
2. Which of these is New Zealand's highest court?
3. What is Royal Assent?
4. Who is New Zealand's head of state?
5. Which statement best describes judicial independence?
Learn more
Primary law
Official explainers
- Ministry of Justice: New Zealand's constitutional system
- Courts of New Zealand: Branches of government
- Courts of New Zealand: Overview of the judiciary
- NZ Parliament: Role of Parliament
- parliament.nz
- Office of the Governor-General
- Governor-General: Roles and functions
- Governor-General: Constitutional role
- Governor-General: Reserve powers
- govt.nz: Governor-General agency listing
- DPMC: Cabinet Manual
- DPMC: Cabinet Manual, Governor-General chapter
Plain-English background
- Te Ara: Parliament
- Te Ara: How Parliament works
- Te Ara: Cabinet government
- Wikipedia: New Zealand House of Representatives
Sources & review: Written by the Citizen Test editorial team from publicly available NZ civics material. Primary sources: govt.nz, legislation.govt.nz, and beehive.govt.nz. Last reviewed .