the Constitution of the Commonwealth of Australia, the separation of powers and the division of powers

What this dot point is asking

QCAA wants you to explain how government power is divided and separated in the Australian Constitution and to evaluate how robustly each doctrine protects against abuse. Expect a 5-8 mark short or extended response in IA1.

The answer

The Constitution

The Constitution of the Commonwealth of Australia is contained in s 9 of the Commonwealth of Australia Constitution Act 1900 (UK). It entered into force on 1 January 1901, federating the Australian colonies into the Commonwealth.

The Constitution divides into eight chapters. The first three establish the three arms of government.

Separation of powers

The Constitution distributes power between three institutions:

Chapter I: legislative power

Section 1 vests legislative power in a Federal Parliament consisting of the Queen, the Senate and the House of Representatives. Section 51 lists the heads of legislative power (40 paragraphs covering taxation, trade and commerce, corporations, defence, marriage, divorce and matrimonial causes, external affairs, etc.).

Chapter II: executive power

Section 61 vests executive power in the Queen, exercisable by the Governor-General. The executive includes the Prime Minister and Cabinet, the federal public service, the Australian Defence Force, and statutory authorities.

Chapter III: judicial power

Section 71 vests the judicial power of the Commonwealth in the High Court of Australia and such other federal courts as Parliament creates. Section 75 sets out the original jurisdiction of the High Court.

Legislative and executive overlap

Australia operates a system of responsible government: ministers must be members of Parliament. The same individuals therefore exercise both legislative and executive power. The strict separation between legislature and executive is therefore largely theoretical in Australia.

Judicial separation is strict

Only Chapter III courts can exercise Commonwealth judicial power. Non-judicial functions cannot be conferred on Chapter III courts. R v Kirby; Ex parte Boilermakers' Society of Australia (1956) 94 CLR 254 (the "Boilermakers' Case") set the rule. Kable v Director of Public Prosecutions (NSW) (1996) 189 CLR 51 extended the principle to state courts exercising federal jurisdiction: a state legislature cannot confer functions on a state court that are repugnant to the court's institutional integrity.

Division of powers

The Constitution divides legislative power between the Commonwealth and the states.

Commonwealth exclusive powers. Powers reserved for the Commonwealth alone:

• defence (s 51(vi)) in practice;
• customs and excise duties (s 90);
• coinage (s 51(xii));
• the seat of government (s 52);
• Commonwealth territories (s 122).

Concurrent powers. Most of s 51. Both the Commonwealth and the states can legislate. Where they conflict, s 109 of the Constitution resolves in favour of the Commonwealth.

State residual powers. Everything not granted to the Commonwealth remains with the states. This includes criminal law (largely), education, health services, transport, environment (in part), property law and family violence law.

The Engineers Case (Amalgamated Society of Engineers v Adelaide Steamship Co Ltd (1920) 28 CLR 129) re-set constitutional interpretation. The High Court rejected reserved state powers and implied immunities, holding that Commonwealth heads of power apply on their natural meaning and prevail in concurrent areas under s 109.

Subsequent High Court decisions have steadily expanded Commonwealth legislative reach through broad interpretation of:

• the external affairs power, s 51(xxix), used to implement treaties (Commonwealth v Tasmania (1983) 158 CLR 1 (the Tasmanian Dam case));
• the corporations power, s 51(xx) (New South Wales v Commonwealth (2006) 229 CLR 1 (the WorkChoices case));
• the financial corporations power (Williams v Commonwealth (2012) 248 CLR 156 narrowed executive spending but not legislative reach).

Evaluation

Strengths.

• the rigid separation of judicial power provides genuine protection against legislative abuse;
• the division of powers preserves a measure of state autonomy;
• the High Court polices both doctrines through original and appellate jurisdiction.

Weaknesses.

• the fusion of legislature and executive limits the separation in practice;
• Commonwealth legislative power has expanded steadily;
• the Senate (designed as a "states' house") increasingly votes on party lines.