政府と法律

Understanding Australia's System of Government: Separation of Powers, 3 Levels & The Constitution

A clear, accessible breakdown of the Westminster parliamentary model, the bicameral Federal Parliament, independent courts, and how laws are made.

11 min read•2350 語

公開日： 2026-08-26

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2026年試験対応版： 2026-09-08

学習の重要ポイント

Australia is a representative parliamentary democracy and a constitutional monarchy.
The Australian Constitution defines the powers of the Commonwealth Government and protects the federal balance.
The Separation of Powers divides authority between the Parliament (Legislative), Government (Executive), and Courts (Judiciary).
Federal Parliament is bicameral: the House of Representatives (Lower House, 151 members) and the Senate (Upper House, 76 members).
To become law, a proposed bill must be passed by both houses of parliament and receive Royal Assent from the Governor-General.

1. Parliamentary Democracy & Constitutional Monarchy Explained

Australia's system of government blends two historic traditions: the British Westminster parliamentary system and the American federal constitutional model.

Representative Democracy: Australian citizens elect Members of Parliament (MPs) and Senators to represent them and make laws on their behalf. If the public is dissatisfied with their leaders, they have the democratic power to vote them out at regular elections.
Constitutional Monarchy: Australia's official Head of State is King Charles III. However, because Australia is a constitutional monarchy, the King acts strictly in accordance with the Australian Constitution and democratic conventions. The King does not participate in day-to-day governance.
The Governor-General: The King's representative in Australia is the Governor-General, appointed on the advice of the Australian Prime Minister. The Governor-General performs vital constitutional duties: signing bills into law (Royal Assent), issuing election writs, and commissioning the Prime Minister.

2. The Separation of Powers: Protecting Citizen Liberties

To prevent any single individual, party, or institution from gaining absolute control, the Australian Constitution divides governance into three independent arms:

1. The Legislative Arm (Parliament)

Who it is: The King (represented by the Governor-General), the Senate, and the House of Representatives.
Function: Debates public policy, introduces new bills, amends existing laws, and scrutinizes the work of government ministers.

2. The Executive Arm (Government Administration)

Who it is: The Governor-General acting on the advice of the Prime Minister and federal Cabinet Ministers.
Function: Puts laws into action, manages national government departments (Treasury, Defense, Foreign Affairs, Home Affairs), and formulates national policies.

3. The Judicial Arm (The Courts)

Who it is: Independent judges appointed to federal, state, and territory courts.
Function: Interprets legislation, applies laws to resolve disputes, and decides criminal guilt or innocence.
Crucial Rule: The Judiciary is strictly independent of Parliament and the Executive. Politicians, ministers, and police cannot tell a magistrate or judge how to decide a case.

3. How a Bill Becomes Law in Federal Parliament

Passing a new federal law requires rigorous democratic review:

Introduction & First Reading: A minister or member introduces a proposed law (called a Bill) into either the House of Representatives or the Senate.
Second Reading & Debate: Members debate the principles and purpose of the Bill and propose detailed amendments.
Third Reading & Vote: The chamber votes on the final version. If approved, the Bill is sent to the other house.
Passage through the Second Chamber: The other chamber (usually the Senate) repeats the three-reading process. Both houses must agree to the exact same wording.
Royal Assent: Once approved by both the House of Representatives and the Senate, the Bill is presented to the Governor-General for signature (Royal Assent). Once signed, the Bill officially becomes an Act of Parliament (Australian Law).

4. The Three Levels of Government: Who Does What?

Australia's three tiers of government share responsibilities without duplication:

Level of Government	Key Leaders	Primary Responsibilities
Federal (Commonwealth)	Prime Minister & Federal Ministers	Defense, Foreign Affairs, Immigration, Currency, Taxation, Trade, Telecommunications, Social Security (Centrelink), Medicare.
State & Territory	Premier (States) or Chief Minister (Territories) & State Ministers	Public Hospitals, State Schools, State Police, Roads & Highways, Prisons, Public Transport, Emergency Services (Fire & Ambulance).
Local (Councils / Shires)	Mayor / Shire President & Local Councillors	Local Roads & Footpaths, Rubbish Collection, Town Planning & Building Permits, Local Parks & Sportsgrounds, Public Libraries, Pet Control.

よくある質問

Can the Prime Minister dismiss the Governor-General?

The Prime Minister can advise the King to appoint or replace a Governor-General. In reverse, the Governor-General holds reserve powers under the Constitution to dismiss a Prime Minister if the government cannot pass budget supply bills or acts unlawfully, as famously occurred in 1975.

What is the Australian Senate's special role?

The Senate is often called the 'States' House' because all six states have equal representation (12 Senators each), ensuring populous states like NSW and Victoria cannot pass laws that disadvantage smaller states like Tasmania and South Australia. It also acts as a 'House of Review'.

1. Parliamentary Democracy & Constitutional Monarchy Explained

Australia's system of government blends two historic traditions: the British Westminster parliamentary system and the American federal constitutional model.

Representative Democracy: Australian citizens elect Members of Parliament (MPs) and Senators to represent them and make laws on their behalf. If the public is dissatisfied with their leaders, they have the democratic power to vote them out at regular elections.
Constitutional Monarchy: Australia's official Head of State is King Charles III. However, because Australia is a constitutional monarchy, the King acts strictly in accordance with the Australian Constitution and democratic conventions. The King does not participate in day-to-day governance.
The Governor-General: The King's representative in Australia is the Governor-General, appointed on the advice of the Australian Prime Minister. The Governor-General performs vital constitutional duties: signing bills into law (Royal Assent), issuing election writs, and commissioning the Prime Minister.

2. The Separation of Powers: Protecting Citizen Liberties

To prevent any single individual, party, or institution from gaining absolute control, the Australian Constitution divides governance into three independent arms:

1. The Legislative Arm (Parliament)

Who it is: The King (represented by the Governor-General), the Senate, and the House of Representatives.
Function: Debates public policy, introduces new bills, amends existing laws, and scrutinizes the work of government ministers.

2. The Executive Arm (Government Administration)

Who it is: The Governor-General acting on the advice of the Prime Minister and federal Cabinet Ministers.
Function: Puts laws into action, manages national government departments (Treasury, Defense, Foreign Affairs, Home Affairs), and formulates national policies.

3. The Judicial Arm (The Courts)

Who it is: Independent judges appointed to federal, state, and territory courts.
Function: Interprets legislation, applies laws to resolve disputes, and decides criminal guilt or innocence.
Crucial Rule: The Judiciary is strictly independent of Parliament and the Executive. Politicians, ministers, and police cannot tell a magistrate or judge how to decide a case.

3. How a Bill Becomes Law in Federal Parliament

Passing a new federal law requires rigorous democratic review:

Introduction & First Reading: A minister or member introduces a proposed law (called a Bill) into either the House of Representatives or the Senate.
Second Reading & Debate: Members debate the principles and purpose of the Bill and propose detailed amendments.
Third Reading & Vote: The chamber votes on the final version. If approved, the Bill is sent to the other house.
Passage through the Second Chamber: The other chamber (usually the Senate) repeats the three-reading process. Both houses must agree to the exact same wording.
Royal Assent: Once approved by both the House of Representatives and the Senate, the Bill is presented to the Governor-General for signature (Royal Assent). Once signed, the Bill officially becomes an Act of Parliament (Australian Law).

4. The Three Levels of Government: Who Does What?

Australia's three tiers of government share responsibilities without duplication:

Level of Government	Key Leaders	Primary Responsibilities
Federal (Commonwealth)	Prime Minister & Federal Ministers	Defense, Foreign Affairs, Immigration, Currency, Taxation, Trade, Telecommunications, Social Security (Centrelink), Medicare.
State & Territory	Premier (States) or Chief Minister (Territories) & State Ministers	Public Hospitals, State Schools, State Police, Roads & Highways, Prisons, Public Transport, Emergency Services (Fire & Ambulance).
Local (Councils / Shires)	Mayor / Shire President & Local Councillors	Local Roads & Footpaths, Rubbish Collection, Town Planning & Building Permits, Local Parks & Sportsgrounds, Public Libraries, Pet Control.

会社概要

Understanding Australia's System of Government: Separation of Powers, 3 Levels & The Constitution

学習の重要ポイント

目次

1. Parliamentary Democracy & Constitutional Monarchy Explained

2. The Separation of Powers: Protecting Citizen Liberties

1. The Legislative Arm (Parliament)

2. The Executive Arm (Government Administration)

3. The Judicial Arm (The Courts)

3. How a Bill Becomes Law in Federal Parliament

4. The Three Levels of Government: Who Does What?

よくある質問

Can the Prime Minister dismiss the Governor-General?

What is the Australian Senate's special role?

Understanding Australia's System of Government: Separation of Powers, 3 Levels & The Constitution

学習の重要ポイント

目次

1. Parliamentary Democracy & Constitutional Monarchy Explained

2. The Separation of Powers: Protecting Citizen Liberties

1. The Legislative Arm (Parliament)

2. The Executive Arm (Government Administration)

3. The Judicial Arm (The Courts)

3. How a Bill Becomes Law in Federal Parliament

4. The Three Levels of Government: Who Does What?

よくある質問

Can the Prime Minister dismiss the Governor-General?

What is the Australian Senate's special role?