QCE Legal Studies - Unit 3 - Governance in Australia
Australian Constitution and Referendum | QCE Legal Studies
Learn QCE Legal Studies governance foundations: the Australian Constitution, sections 51, 109 and 128, referendum difficulty and constitutional change.
Updated 2026-05-18 - 6 min read
QCAA official coverage - Legal Studies 2025 v1.3
Exact syllabus points covered
- Describe key features of the Australian Constitution, including the division of powers in s 51 and s 109, and the referendum process in s 128.
- Analyse challenges of changing the Australian Constitution using past referenda as examples.
- Comprehend legal terminology including democracy, the Australian Constitution and referendum.
The Australian Constitution is the rulebook for the Commonwealth legal and political system. It creates the federal Parliament, gives law-making powers to the Commonwealth, preserves the role of the states, and gives the High Court authority to resolve constitutional disputes. In Legal Studies, the Constitution matters because it explains where government power comes from, where that power is limited, and why legal change can be difficult.
Original Sylligence diagram for legal constitution framework.
Why the Constitution matters
The Constitution is not just a historical document from Federation. It is a legal source that shapes law-making every day. If the Commonwealth Parliament wants to pass a law, it usually needs to connect that law to a constitutional head of power. If a state law conflicts with a valid Commonwealth law, the Constitution decides which law prevails. If Australians want to alter the constitutional text, they must use the referendum process.
Three sections come up repeatedly in Unit 3:
| Section | What it does | Why Legal Studies cares | | --- | --- | --- | | Section 51 | lists many Commonwealth law-making powers | explains federal legislative authority | | Section 109 | resolves inconsistency between valid Commonwealth and state laws | shows Commonwealth law can prevail | | Section 128 | sets the referendum process | explains why constitutional change is hard |
Section 51 and Commonwealth power
Section 51 lists areas where the Commonwealth Parliament can make laws. Examples include trade and commerce, taxation, defence, external affairs, marriage, corporations and immigration. Some topics are not written neatly into section 51, so governments and courts often argue about whether a law fits inside a head of power.
That is why High Court interpretation matters. A short phrase in the Constitution can become the foundation for major law-making if the High Court interprets it broadly. For example, the external affairs power has been important where Australia enters international agreements and then passes domestic legislation connected to those obligations.
Section 109 and inconsistency
Federalism means state and Commonwealth governments can both operate in Australia. Sometimes their laws overlap. Section 109 says that if a state law is inconsistent with a valid Commonwealth law, the Commonwealth law prevails and the state law is invalid to the extent of the inconsistency.
That last phrase is important. The whole state Act does not necessarily disappear. Only the conflicting part is pushed aside for as long as the inconsistency exists.
Section 128 and referenda
Section 128 explains how the Constitution can be changed. A proposal must pass through the Commonwealth Parliament and then be approved by Australian voters in a referendum.
For a referendum to succeed, it needs a double majority:
- a national majority of voters across Australia
- a majority of voters in a majority of states, meaning at least four out of six states
This is deliberately demanding. It protects constitutional stability by making sure change has broad national and state support. The trade-off is that even popular reform can fail if the proposal is unclear, politically contested or not supported across enough states.
Why referenda often fail
Referenda can fail for several reasons: voters may not understand the proposal, the wording may sound too technical or risky, political parties may campaign against each other, states may worry about losing power, or voters may prefer the status quo when uncertain.
The 1999 republic referendum is a useful example. Many Australians supported the broad idea of a republic, but the specific model for appointing the head of state was contested. That matters for Legal Studies because it shows the difference between supporting a general reform and approving the legal mechanism used to achieve it.
Historically, constitutional change has been rare. Since Federation, Australians have voted on 45 constitutional alteration proposals and only eight have passed. That statistic is useful because it proves the double majority is not just a technical rule; it is a major barrier to reform.
Common failure factors include:
| Factor | Why it matters | | --- | --- | | Double majority | A proposal can win the national vote but still fail if fewer than four states vote yes. | | Lack of bipartisan support | If major parties campaign against each other, voters receive conflicting messages. | | Confusing information | Voters may vote no when the model, wording or consequences are unclear. | | Timing | Referendums held near elections can be overshadowed by party politics. | | Voter conservatism | If people are uncertain, they often prefer the existing constitutional position. |
Case study: 1999 republic referendum
The 1999 republic proposal asked voters whether Australia should replace the Queen and Governor-General with a President appointed by a two-thirds majority of Commonwealth Parliament. It did not pass in any state and failed nationally.
The case is useful because it was not simply a debate about whether Australia should become a republic. Much of the controversy was about the model. Some voters wanted a republic but rejected parliamentary appointment of the President. Others preferred keeping the constitutional monarchy. The result shows why constitutional reform needs a clear legal mechanism, not just popular interest in a broad idea.
You can also mention the 2023 Voice referendum as a modern example of the same structural difficulty: a constitutional proposal can be politically significant, widely debated and still fail if the double majority is not achieved.
Worked example
Evaluating constitutional change
A strong Legal Studies answer does more than say "referenda are hard". It links the difficulty to legal criteria. Stability can promote certainty and the rule of law. However, difficulty can also block reform that might improve justice, equality or democratic representation.