← The hardest concepts in Australian law
In one breath
The Commonwealth Parliament has only the powers the Constitution lists, chiefly in section 51, and a law is valid if it is sufficiently connected with the subject of one of them. The powers are read broadly and without a general reserve of State matters, so a law about corporations or about treaty obligations can reach deep into areas the States also govern.
The picture
The ring of keys
The Commonwealth is like a caretaker with a ring of keys, each cut for one door: defence, trade and commerce, taxation, corporations, external affairs and the rest. The caretaker may use any key that turns the lock, and a key opens its door fully, not just a crack. It does not matter that the door leads into a room the neighbour also looks after, or that the caretaker had other reasons for going in. If the key fits, the door opens.
But the caretaker holds only the keys on the ring. A door without a key cannot be opened however much the building needs it. So a court asks which door the law is going through, and whether the law has a real connection with that door. It looks at what the law does in its legal operation and effect, not at the motives behind it, and gives each key its full natural reach. A law can go through more than one door at once.
Where the picture stops working
A key either turns or does not, but the connection test is a matter of degree, and the courts differ on how close a link is enough. Some keys are also narrower than they look: the treaty power supports a law only if it genuinely implements the treaty. And other parts of the Constitution, such as the just-terms guarantee, restrict what any key may do.
How it really works
- 1Place the rule. It is constitutional and federal. The Commonwealth has only the listed powers and the States hold the rest, so the question is always about the Commonwealth’s reach.
- 2Characterise the law. Work out what it does by its legal operation and effect, and find the head of power it relies on. It is not enough that the law helps some wider aim.
- 3Test the connection. Is the law sufficiently connected with the subject matter of the power, not remote or tenuous? Powers are read broadly, and the Court has rejected the idea of a protected State area that narrows them.
- 4For the corporations power, ask whether the law regulates the activities, functions or relationships of trading or financial corporations, including their relationships with employees, or persons connected with them.
- 5For the external affairs power, ask whether the law implements a binding treaty in a way reasonably capable of being seen as appropriate and adapted to it, or deals with a matter of international concern.
Why people get it wrong
- Looking for one large power that covers everything. Each law is tested against the heads of power on its own.
- Assuming that State territory is fenced off from Commonwealth laws. The Engineers case rejected that approach.
- Judging a law by its motive. The courts look at its legal effect.
- Treating a treaty as automatic power. There must be a real implementation, not a pretext.
- Reading the corporations power as a power over all business. It reaches only the listed kinds of corporation.
A worked example
The facts are invented
Parliament passes the Marine Wellbeing Act, which requires any trading corporation that operates fishing vessels to give its crews paid rest breaks. The Act regulates the relationship between constitutional corporations and their employees, so the corporations power supports it, even though the States also regulate employment.
Change the facts: the Act also requires sole traders who own fishing boats to give their crews the same breaks. A sole trader is not a constitutional corporation, so the corporations power does not reach that part; it needs another head of power, or it is invalid to that extent. Change them again: another section protects a reef under a treaty that Australia has ratified. That can rest on the external affairs power, provided it genuinely carries the treaty into effect.
Try it
Parliament passes a law regulating the working conditions of employees of trading corporations. A State argues that employment is a State matter and the Commonwealth cannot interfere. How does the argument fare?
Landmark authorities
Read the sources themselves; this list is a starting point.
- Amalgamated Society of Engineers v Adelaide Steamship Co Ltd, (1920) 28 CLR 129
- R v Burgess; Ex parte Henry, (1936) 55 CLR 608
- Commonwealth v Tasmania, (1983) 158 CLR 1
- New South Wales v Commonwealth, (2006) 229 CLR 1
Where to go next
Courses
Dictionary
More hard concepts in Australia law
- Section 109: when Commonwealth and State laws clash (Constitutional law)
- The separation of judicial power and the Boilermakers principle (Constitutional law)
- The implied freedom of political communication (Constitutional law)
- The guarantee of acquisition on just terms (Constitutional law)
- State and federal courts: Wakim and Kable (Constitutional law)
This page is an educational overview. It is not legal advice and not a substitute for the sources: the statute, the rule, the case itself. Australia is a federation: the Commonwealth, the six States and the Territories each make law, and the High Court is the final court for all of it. The common law, by contrast, is one law across the country. Each page says whether the rule is constitutional, federal or common law shared by every jurisdiction, or State-by-State legislation that varies, and flags where the States and Territories differ. Each page states the usual formulation of the rule and names landmark decisions; check the primary sources of your own jurisdiction before relying on any rule.