Hard Concepts in Law · Australia
The hardest concepts in Australian law
20 ideas, 8 areas of law, one picture for each.
These are the ideas that students find hard, across 8 areas of law. Each one has its own page with an everyday picture of how the rule is built, the usual mistakes, a worked example and a trap question.
Step 1Constitutional law
Section 109: when Commonwealth and State laws clash
The eclipse and the sun
When a valid State law is inconsistent with a valid Commonwealth law, section 109 of the Constitution makes the Commonwealth law prevail and the State law inoperative to the extent of the inconsistency. Inconsistency can arise because the two laws cannot both be obeyed, because one takes away a right the other confers, or because the Commonwealth law was meant to be the complete statement on the subject.
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Step 2Constitutional law
The separation of judicial power and the Boilermakers principle
The kitchen and the dining room
Chapter III of the Constitution gives the judicial power of the Commonwealth only to courts, and the Boilermakers principle adds the reverse: a federal court may exercise nothing but judicial power, apart from what is incidental to it. The result is a double wall that keeps courts out of the work of governing and keeps governing bodies out of the work of judging.
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Step 3Constitutional law
The implied freedom of political communication
The window in the wall
The Australian Constitution contains no general bill of rights, but the High Court has held that the system of representative government it creates implies a limit on legislative power: laws may not burden communication about government and political matters unless the burden is justified. It is a limit on law-making power, not a personal right to speak, and it does not protect speech as such.
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Step 4Constitutional law
The guarantee of acquisition on just terms
The market stall and the till
Section 51(xxxi) of the Constitution lets the Commonwealth Parliament acquire property, but only on just terms, and the High Court reads that condition as a guarantee that limits the Commonwealth’s other powers as well. A law is caught only if it takes some proprietary benefit, however slight, from the owner, and not merely because it removes or regulates a right.
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Step 5Constitutional law
The Commonwealth’s heads of power
The ring of keys
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.
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Step 6Constitutional law
State and federal courts: Wakim and Kable
The teacher on loan
Australia has federal courts and State courts, and the Constitution lets Parliament invest State courts with federal jurisdiction but does not let federal courts be given State jurisdiction. The High Court has also held that State courts must remain fit to exercise federal jurisdiction, so a State Parliament cannot give its courts functions that would undermine their independence and integrity.
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Step 7Administrative law
Jurisdictional error and privative clauses
The paddock and its fence
A decision-maker who stays within the limits of the power given to them may still make mistakes, but a decision-maker who steps outside those limits commits a jurisdictional error and the decision is treated as invalid. Parliament cannot remove the courts’ power to review for jurisdictional error, so a clause saying that decisions are final is read as protecting only decisions made within the limits of the power.
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Step 8Administrative law
Procedural fairness
The thermostat
Procedural fairness, once called natural justice, is a common law duty on a person making a decision that affects another’s rights or interests to hear that person fairly and to decide without bias. The duty is presumed to apply, can be removed only by clear statutory words, and has content that varies with the circumstances.
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Step 9Legal method
Precedent in the High Court
The bush track
The High Court is the final court on every question of law in Australia, is not strictly bound by its own earlier decisions, and treats the common law as a single national body of law that it shapes for itself, with decisions from England and elsewhere only persuasive. Lower courts follow the High Court, and intermediate appellate courts follow one another unless convinced that an earlier decision is plainly wrong.
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Step 10Property law
Native title and the common law
The translator and the original text
The common law of Australia recognises native title: the rights and interests of Aboriginal and Torres Strait Islander peoples in land and waters under their own traditional laws and customs, which survived the Crown’s acquisition of sovereignty. These rights are recognised by the common law, not created by it, they can be extinguished only by valid government acts, and a national statute now governs their recognition and protection.
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Step 11Property law
Torrens title and indefeasibility
The seating chart at the theatre
Under the Torrens system, found in every Australian State and Territory, title to land depends on registration, so the person on the register holds an indefeasible title subject to a short list of exceptions. The register is meant to be the one place to look, which is why a registered owner generally prevails over earlier unregistered interests, even when the document that led to registration was a forgery, so long as the registered owner took no part in the fraud.
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Step 12Equity
Equitable estoppel
The scaffold around a half-built wall
Equitable estoppel prevents a person from going back on an assumption they encouraged another to adopt, when the other has relied on it to their detriment and it would be unconscionable to depart from it. The remedy is not fixed: the court gives the minimum needed to do justice, which may be less than the promise.
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Step 13Equity
Unconscionable conduct
The seesaw and the push
In equity, a transaction can be set aside when one party was under a special disadvantage that seriously affected their judgment, and the stronger party knew of it and took advantage of it. A statute also forbids unconscionable conduct in trade or commerce, and it operates alongside the equitable rule.
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Step 14Equity
Accessory liability and strangers to a trust
The pawnbroker and the courier
A person who is not a trustee or fiduciary can still be liable in equity if they receive trust property knowing it was transferred in breach of trust, or if they knowingly help a trustee or fiduciary in a dishonest and fraudulent breach. These are the two limbs of the rule in Barnes v Addy, and Australian courts keep it as the test, with knowledge, not carelessness, as the trigger.
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Step 15Tort law
The duty of care and salient features
The surveyor’s map
Negligence requires a duty of care, and the High Court has said there is no single test for when one exists: reasonable foreseeability is necessary but not enough. In new situations, especially pure economic loss and omissions, courts look at the salient features of the relationship, such as vulnerability, control, knowledge and coherence with the rest of the law.
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Step 16Tort law
Causation and the scope of liability
The turnstile and the usher
To recover in negligence the plaintiff must show that the breach caused the harm, and in the civil liability legislation of most jurisdictions that means two steps: the breach must have been a necessary condition of the harm, and it must be appropriate for the defendant’s responsibility to extend to it. At common law the High Court has said that the “but for” test is not the only test and that causation involves common sense and value judgments.
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Step 17Tort law
Occupiers’ liability
The partition wall that was knocked down
At common law in Australia the liability of an occupier of premises is not a separate regime with its own classes of visitor; it is part of the law of negligence, so the occupier owes a duty to take reasonable care to avoid foreseeable risks of injury to people who come onto the land. The old categories of invitee, licensee and trespasser no longer decide the duty, although the visitor’s circumstances still affect what care is reasonable.
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Step 18Contract law
The parol evidence rule and the reading of contracts
The darkroom print and the contact sheet
When parties record their agreement in a written contract, the parol evidence rule stops them using earlier or outside material to add to, vary or contradict it, and the contract is read objectively, for what a reasonable person in the parties’ position would take the words to mean. Surrounding circumstances can help to understand the words, but the parties’ private intentions and their negotiations generally cannot.
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Step 19Contract law
Implied terms
The keystone
Where a contract is silent, a court may sometimes imply a term, either in fact, to give the particular contract the effect the parties must have intended, or in law, as a standard feature of a type of contract. Implication fills a gap out of necessity; it is never a way to improve a bargain or to rewrite what the parties said.
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Step 20Criminal law
Criminal responsibility: the Code states and the common law states
The recipe book and the family kitchen
Australia has no single criminal law: each State and Territory makes its own, and Queensland, Western Australia, Tasmania and the Northern Territory write the general principles into a Criminal Code, while New South Wales, Victoria and South Australia rely mainly on the common law with statutes layered on top. Every offence still has a physical element and a fault element, but the rules on accident, mistake and defences sit in different places and can lead to different answers.
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Read this first
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.
These pages are educational overviews. They are not legal advice and not a substitute for the primary sources.