Proportionality analysis 

Almost no right is treated as absolute. Once a right is engaged, the harder question is usually whether a particular law or decision that limits it can be justified. Proportionality analysis is the structured method Australian courts and tribunals use to answer that question, whether the right arises under a constitutional provision, a jurisdiction-specific human rights charter or Act, or another legal source that asks whether a limit on a right or freedom is acceptable.

Why a structured test rather than simple balancing

It is tempting to think a court should simply weigh the importance of the right against the importance of the competing public interest and decide which is heavier. Proportionality analysis deliberately rejects that approach in favour of a structured, staged inquiry, for several reasons.

First, an unstructured balancing exercise gives very little guidance to a decision-maker or to the parties in advance — it invites the decision-maker's own view of relative importance to do all the work, with little discipline on how that view is reached. Second, it makes reasoning hard to test and hard to review: a bare conclusion that one interest "outweighs" another is difficult to challenge on appeal because there is no intermediate step at which the reasoning can be shown to be wrong. A staged test, by contrast, isolates distinct questions — purpose, connection, and necessity — so that a flaw in the government's justification can be identified precisely, at the stage where it actually arises, rather than buried in an undifferentiated conclusion.

The structure of the test

Although the precise formulation differs depending on the legal source of the test, a proportionality inquiry typically asks a sequence of questions, matching the structured approach a majority of the High Court adopted in McCloy v New South Wales (2015) 257 CLR 178.¹

1. Legitimate purpose. Does the measure that limits the right pursue a purpose that the law recognises as legitimate? A purpose that is itself impermissible — for example, a purpose that exists only to disadvantage a particular group — cannot justify a limit on a right, however effective the measure is at achieving it.
2. Rational connection. Is the measure actually capable of achieving that purpose, as a matter of logic and evidence? A measure that does not rationally advance the purpose it is said to serve cannot be justified by reference to that purpose, no matter how legitimate the purpose is in the abstract.
3. Reasonable necessity (sometimes called minimal impairment). Does the measure go no further than is reasonably necessary to achieve the purpose? If a less restrictive measure was reasonably available and would have achieved the same purpose with less interference with the right, that suggests the measure chosen is not proportionate.

Some formulations add a further overall step, sometimes described as proportionality in the strict sense, which asks whether the burden placed on the right is justified in light of the benefit gained, even after the earlier stages are satisfied. Not every version of the test includes this final step explicitly, but it captures the same underlying concern: that a measure can pass the first three stages and still impose a burden on the right that is out of proportion to what is actually gained.

The standing of the structure is now in question

In Hopper v Victoria [2026] HCA 11² Edelman J said at [86] that of these questions "[o]n any view, the first question in this structure is redundant" and that "[t]he third question also has little role to play", and at [87] that these defects, "together with the antipathy towards any test based upon structured proportionality now expressed by a majority of this Court, may mean that a test based on structured proportionality should now be treated as dead". That is one Justice, not the Court, and what he would keep is the second question — the transparency of asking whether the burden is reasonably capable of being seen as necessary.

The fact that carries more weight is what the majority did. The joint reasons of Gageler CJ, Gordon, Jagot and Beech-Jones JJ decide the implied freedom question without using the language of proportionality at all, framing it instead as whether the burden is justified in pursuit of a legitimate purpose. No majority has held the stages to be wrong, so McCloy still states what it decided. But do not present the stages as the test the law requires: state the question, use the stages as a tool for answering it, and say that is what you are doing.

Working through the stages in order

The staged structure is not a formality — courts generally work through the stages in sequence, and a measure that fails an earlier stage does not need to be tested against later ones. A measure pursuing an illegitimate purpose cannot be saved by showing it was carefully tailored; a measure with no rational connection to a legitimate purpose cannot be saved by showing there was no less restrictive alternative. Each stage is a genuine hurdle, not simply one factor in an overall impression.

Where the test is used

Proportionality reasoning of this kind commonly arises where a constitutional provision constrains legislative or executive power that touches on a right or freedom, and it is also built into the operative provisions of a jurisdiction-specific human rights charter or Act where one exists, which typically asks whether a limit on a protected right is a proportionate limit that can be demonstrably justified. The underlying structure — purpose, connection, necessity — recurs across these contexts even though the precise legal source and wording of the test varies.

Two 2025 decisions settle how the stages should be used. In Babet v Commonwealth of Australia [2025] HCA 21³ Gageler CJ and Jagot J described "the flexible application of all or any of the steps of structured proportionality" as a "tool of analysis", "express or ritual invocation of which is by no means necessary in every case"; Gordon J agreed at [72] that it was not "necessary (or helpful)" to apply the three steps there.

Ravbar v Commonwealth of Australia (2025) 99 ALJR 1000⁴ puts it most directly: Jagot J held that no description of the analysis "can or should be understood as requiring formulaic recitation of each of its three elements, still less recitation of the labels". Beech-Jones J applied the test anyway — "[i]n circumstances where the parties framed their submissions in this case solely by reference to the approach in McCloy" — which is what using it as a tool looks like.

Applying this in a problem question

1. Identify the right that is said to be limited, and the measure that limits it.
2. Identify the source of the proportionality test that applies on these facts (constitutional, charter-based, or otherwise), since the exact formulation can differ.
3. Ask whether the measure pursues a legitimate purpose, and be specific about what that purpose actually is.
4. Ask whether the measure is rationally connected to that purpose.
5. Ask whether the measure goes no further than reasonably necessary, and identify any less restrictive alternative that was reasonably available.
6. Work through the stages in order, and do not skip ahead to an overall impression before testing each stage on its own terms.