State courts and the Kable principle

The Kable principle protects State courts rather than the people who come before them. Fix first on the court and the function a statute gives it, then ask whether that function damages the court as a body fit to hold federal judicial power.

The idea

The Constitution says little about State courts on its face. Under s 71 and s 77(iii) the judicial power of the Commonwealth may be vested in State courts, so those courts form part of one integrated national system. Because there are not two grades of federal judicial power, no State Parliament may legislate to undermine a State court's role as a repository of that power (Kable, McHugh J at 115).

The doctrine protects the institution rather than the person before it. In Kable the Community Protection Act let the New South Wales Supreme Court detain one named man, Gregory Kable, on the balance of probabilities for feared future violence. The invalidity lay not in keeping a man in prison but in making the Supreme Court the instrument of a legislative plan (Kable, McHugh J at 122).

The principle reaches every court of the States. It is not confined to Supreme Courts or to courts already vested with federal jurisdiction (Totani, French CJ). The Constitution has also withdrawn from each State the power to abolish its Supreme Court. This is because s 73 gives the High Court appellate jurisdiction that assumes a State Supreme Court continues to exist (Kable, McHugh J at 111).

Where it comes from

The doctrine begins with Kable. McHugh J held that State courts hold federal judicial power under s 71 and s 77(iii) as part of one integrated system, so no State Parliament may legislate to undermine their role as repositories of that power (Kable, McHugh J at 115). The High Court spent the next two decades refining the idea across Totani, Wainohu and Garlett.

The settled statement now comes from North Australian Aboriginal Justice Agency, which drew the principles together into five propositions. The first is the governing rule. A State legislature cannot confer on a State court a function which substantially impairs its institutional integrity as a repository of federal judicial power (NAAJA at 593). Institutional integrity means the defining and essential characteristics of a court, and those five propositions now serve as the working test for the whole topic.

The anchor

Kable v Director of Public Prosecutions (NSW) is the source of the principle. A statute impairs institutional integrity where it makes the Supreme Court the instrument of a legislative plan to imprison a named person by a process far removed from the ordinary judicial process (McHugh J at 122). Every later case reads through that idea.

How it is examined

This is a problem topic and a dependable one. State courts and Kable appear in four of the seven finals since 2024, carrying 15 to 20 marks and turning up in every paper across that period. The usual fact pattern hands a State court or a State judge a new statutory function and asks whether it is valid.

The recurring hook is the mandatory direction. A power that says the court must make an order once an executive condition is met is the classic Totani pattern, so quote the mandatory word and ask whether the court decides anything of substance. The other regulars are closed material that hides the case from the affected party, a judge seated on a government body, and a protective detention regime that looks harsh yet leaves the court a real choice. The marks concentrate on the executive determination point and on conceding validity where the court genuinely decides.

How to argue it

Work the problem in a fixed order.

Identify the State court and the function the statute confers on it or on its judges. Kable protects State courts as repositories of federal judicial power under s 71 and s 77(iii).
State the test. Ask whether the function substantially impairs the court's institutional integrity as a repository of federal judicial power (NAAJA).
Weigh the function against the defining characteristics of a court, being the reality and appearance of independence and impartiality, procedural fairness, the open court principle and the general giving of reasons (Wainohu). No single characteristic decides the question.
Run the executive determination question. The plaintiff will argue the court merely gives the neutral colour of a judicial decision to what an executive declaration has already settled. The State's response will be that the court decides the operative criteria itself and keeps genuine adjudicative work. The line falls at the point where the court's real work begins (Totani).
Test any personal capacity label against Wainohu. The State bears the argument that the persona designata dressing removes the function from Kable, and the label carries little weight where the function is conferred by virtue of judicial office.
Test any protective regime against Garlett before condemning it. Where the court genuinely decides on evidence by an ordinary judicial process, concede validity and move on. Mandatory language does not condemn the scheme where the judicial evaluation is essential to the order (Garlett).

The conclusion can grade its confidence. Where the executive declaration supplies the essential foundation of the order the stronger view is invalidity, and where the court keeps a real choice on the evidence the balance favours validity.

Practice problems

One hundred exam-style problems across twelve topics. Pick a topic, read the problem, write your own answer in IRAC, then reveal the Pass and H1 exemplars and the examiner's comments. Step through in order or jump to a random one. Nothing you type is saved or sent anywhere.

Topic

Loading problems…

The trap

The costly mistake is to treat a preserved discretion as the answer in either direction. Students who meet a protective or continuing detention regime reach reflexively for Kable. Garlett upheld exactly such a scheme. The order there was mandatory once the statutory criteria were made out, and validity rested on the judicial evaluation being essential to it. Run the adjudication analysis first and concede validity where the court genuinely decides.

The opposite error is to stop once a genuine discretion is found and declare the scheme safe. A function can keep a real choice and still fall on another characteristic. This is because procedural fairness is a defining characteristic in the Wainohu list, so a scheme that hides the case from the affected party can impair institutional integrity even where the discretion is genuine.

One further slip is to argue from public confidence. McHugh J spoke of bringing the administration of justice into disrepute. French CJ warned that public confidence is not the measure of compliance with the Constitution (Totani). State the test as substantial impairment of institutional integrity.

Key authorities

Kable v DPP (NSW) — No State may legislate to undermine a State court's role as a repository of federal judicial power, and the vice was making the court the instrument of a legislative plan.★
North Australian Aboriginal Justice Agency — Restates the settled principle that a State cannot confer a function which substantially impairs a court's institutional integrity.
South Australia v Totani — A court is impermissibly enlisted where it gives the neutral colour of a judicial decision to what an executive declaration has already determined.★
Wainohu v New South Wales — The persona designata label carries little weight, and a function requiring a judge to declare organisations criminal without reasons impairs institutional integrity.★
Garlett v Western Australia — A continuing detention regime survives where the court decides on evidence by judicial process, the judicial evaluation of the statutory criteria being essential to the order.★
Constitution ss 71 and 77(iii) — Allow the judicial power of the Commonwealth to be vested in State courts, making them part of one integrated system.
Constitution s 73 — Gives the High Court appellate jurisdiction that assumes each State Supreme Court continues to exist, so a State cannot abolish it.