Sometimes a change comes with a soft breeze. Other times, it is a tempest.
A mere five days after Gageler CJ’s swearing in as the new Chief Justice of the High Court of Australia, every indication is that Australia is witnessing the latter form of dramatic shift in juridical weather.
On the 8th of November, the High Court delivered a landmark ruling that the indefinite detention regime under the Migration Act is unconstitutional, overruling the 2004 decision of Al-Kateb. At the end of the second of two days of hearing, the High Court announced that ‘at least a majority’ of the court had determined that the Court should make orders declaring the detention of the plaintiff unlawful, and ordered a writ of habeas corpus be issued requiring his immediate release.
The decision, both in form and substance, sent shockwaves through Australia’s legal and political establishment. In adopting the relatively uncommon procedure of issuing orders immediately following the hearing (with reasons to follow), a gap was created where politicians rushed to come up with a legislative response in the absence of any clearly articulated constitutional rules. The ongoing political point scoring and misrepresentation of the decision since the release of the reasons on the 28th of November have, however, highlighted that the real political concern is not the reality of the decision but the way in which it can be distorted to advance political agendas. In particular, the Opposition has relentlessly sought to use the decision to portray the centre-left Labor Government as being ‘soft’ on immigration, while the Government has squirmed to avoid being wedged on the issue. In an island country, where several elections in the last 20 years have been ostensibly won and lost over concerns of ‘illegal’ immigration, this decision has been political dynamite. It is likely that the fall-out will continue well into the new year.
The Constitutional Stain of Al-Kateb
This case is one of those constitutional law cases that are likely to be more significant for their political implications than their legal ones. The 2004 High Court decision Al-Kateb v Goodwin, that indefinite detention of a stateless person can be constitutionally permissible, has long been seen as a dark stain on the constitutional landscape of contemporary Australian jurisprudence. Over the last twenty years, it has become increasingly difficult to reconcile with the development of related legal doctrines.
The legislative regime involved in Al-Kateb had been introduced a decade earlier, in September 1994, to create a system of mandatory administrative detention of unlawful non-citizens (relevantly, people who entered Australia without permission in the form of a visa, or whose permission had expired). At the time, Australia stood alone amongst Western nations as the only country that pursued such a policy of mandatory administrative detention.
Critically, this regime required that the unlawful non-citizen ‘must be kept in immigration detention until’ the occurrence of one of several specified events – such as a grant of a visa, or removal from Australia. The key question in Al Kateb was, then, whether such detention continued to be constitutional in instances where there were no reasonable prospects for the removal of the individual.
By 4:3 majority, the High Court in that case held that, on its proper construction, the statutory regime required the ongoing detention of such an individual, and that such ongoing indefinite detention did not contravene the constitutional separation of powers under Chapter III of the Constitution.
The decision was subject to immediate, significant, and sustained critique, described for example, by Meagher as a ‘stunning triumph of constitutional form over substance.’ However, it is critical to appreciate both the juridical and political context in which the decision occurred. Politically, the issue of immigration was a matter of red-hot concern, with the Howard Government achieving a controversial come-from-behind victory in the prior election in 2004 largely off the back of the ‘children overboard’ Tampa affair. Juridically, the Court had reached a modern peak of conservative ideology, following nearly a decade of conservative appointments in response to the ‘judicial activism’ of the Mason court (which had delivered seminal decisions such as Mabo and Kable). In this context, the decision to uphold the indefinite detention regime was perhaps entirely predictable from a realist perspective.
The Withering and Re-Emergence of Lim
The doctrinal issue with Al-Kateb has long been that – when this political context is stripped away – the decision appears inconsistent, indeed incoherent, when assessed against existing and subsequent legal doctrine.
Of particular significance was the 1992 decision of Chu Kheng Lim, where the Court had upheld the validity of an earlier, more limited, immigration detention regime. Importantly, that decision contained three statements of background principle which have come to be regarded as authoritative.
The first principle was a reiteration that the fundamental and long-established principle, that no person may be detained by the executive absent statutory authority or judicial mandate, applies equally to citizen and alien alike. Secondly, the plurality confirmed that – exceptional cases aside – involuntary detention ‘is penal or punitive in character and … exists only as an incident of the exclusively judicial function of adjudging and punishing criminal guilt’ (p27). Thirdly, the plurality held that the only relevant difference in this context between a non-alien and an alien ‘lies in the vulnerability of the alien to exclusion or deportation’. In light of these principles, the plurality held that a detention regime such as that considered in Lim, will be valid only to the extent that such detention is necessary for purposes of deportation or to enable an application for an entry permit to be made and considered (p33). In all other cases, such detention will be seen as a form of constitutionally prohibited extra-judicial punishment. In NZYQ, the Court expressed the principle in Lim as requiring:
‘…that a law enacted by the Commonwealth Parliament which authorises the detention of a person, other than through the exercise by a court of the judicial power of the Commonwealth in the performance of the function of adjudging and punishing criminal guilt, will contravene Ch III of the Constitution unless the law is reasonably capable of being seen to be necessary for a legitimate and non-punitive purpose. In other words, detention is penal or punitive unless justified as otherwise.’ 
Importantly, the constitutional principle that was so formulated and applied in Lim was not disavowed by the majority in Al-Kateb. Indeed, as the Court in NZYQ observed, nothing ‘said in Al-Kateb has been taken subsequently to detract from the significance of Lim’ .
The failure of the court in Al-Kateb to adequately grabble with the connection between the means of detention and an achievable statutory purpose has long been seen as creating a significant tension between Al-Kateb and Lim. The consequence has been that, as the Court in NZYQ notes, that ‘constitutional holding in Al-Kateb has come increasingly to appear as an outlier in the stream of authority which has flowed from Lim’ . This tension has only become more acute in recent years when as the Lim principle has been ‘repeatedly acknowledged and frequently applied’ . Of particular note have been the recent decisions in Alexander v Minister for Home Affairs (2022) and Benbrika v Minister for Home Affairs (2023) where the court applied Lim to invalidate citizenship striping provisions. After a long period when Lim seemed to provide a hollow constitutional protection, it has suddenly – over the last twelve months – grown teeth. In this context, Al-Kateb looked increasingly as an outlier, needing only an appropriate test case before Lim would finally bite.
The Refutation that is NZYQ
As the Court was at pains to confirm, NZYQ was the first time ‘that there was shown to be a state of facts which made questions about reopening and overruling Al-Kateb necessary’ . The plaintiff in the case was a stateless Rohingya Muslim, born in Myanmar, who arrived in Australia by boat in 2012. The plaintiff was granted a bridging visa in 2014. In 2016, the plaintiff pleaded guilty to a sexual offence against a child and was sentenced to imprisonment for five years. Upon his release on parole in 2018, he was taken again into immigration detention. In 2020, the plaintiff’s application for a permanent protection visa was rejected on the grounds that despite having well-founded fear of persecution in Myanmar, he was reasonably considered a danger to the Australian community. By 2022, all avenues to challenge that determination were exhausted, and the plaintiff wrote to the Minister requesting his removal from Australia.
It soon became apparent that no country in the world was appropriate or willing to receive the plaintiff. As a result, in April 2023, the plaintiff initiated proceedings in the original jurisdiction of the High Court directly challenging both the statutory construction and constitutional findings of Al-Kateb regarding indefinite detention in circumstances where there was no reasonable prospect of removal.
Given the opportunity to directly confront the finding in Al-Kateb, the Court did not hold back. When the reasons were published on the 28th of November (less than three weeks after the hearing and pronouncement of orders) it was revealed that the court unanimously concluded that the finding in Al-Kateb (that as ‘long as the purpose of the detention is to make the alien available for deportation … the detention is non-punitive’ ( McHugh J)) represented ‘an incomplete and, accordingly, inaccurate statement of the applicable principle’ . Interestingly, despite being formally a joint judgment, the reasons revealed that the justices took two different approaches to reach that conclusion, one route taken by Edelman J, and another route taken by the other six justices.
The Approach of the Six
For six members of the court (Gageler CJ, Gordon, Steward, Gleeson, Jagot and Beech-Jones JJ) Lim required an assessment ‘of both means and ends, and the relationship between the two’ . In circumstances where there is no real prospect of removal, it can no longer reasonably be said that detention continues to be for the purposes of removal, as
The Lim principle would be devoid of substance were it enough to justify detention … that the detention be designed to achieve an identified legislative objective that there is no real prospect of achieving in the reasonably foreseeable future. 
It relevantly follows that if the only purpose relevantly justifying executive detention is removal from Australia, then, in the absence of any real prospect of removal in the reasonably foreseeable future, such detention cannot be justified.
The Approach of Edelman J
Edelman J articulated a slightly different approach that sought to disaggregate the concept of punishment as used in Lim. His approach begins with the premise that Lim uses the concept of punishment in two different senses. Firstly, he argued that Lim prohibits any form of executive punishment, in the sense that ‘harsh consequences are imposed based upon classic criminal notions of just desert’ . Secondly, he argues that detention will be ‘prima facie’ punitive, and thus illegitimate, where the law ‘employs means that are disproportionate to its legitimate purpose’ . In NZYQ, the indefinite detention had become punitive as the proportionality requirement of Lim had been effectively ignored so that the unobtainable end of removal no longer justified the means of detention.
It is worth noting that the precise implication and status of this ‘jointish judgment’ on the appropriate approach remains unclear as this appears to be the first time the High Court has adopted this mode of aggregating a joint judgment. Normally, where a judge agrees with the orders given but disagrees on the approach, a separate concurring opinion is given. The mode followed here is exceedingly rare. Nevertheless, while this artifact is of interest to judicial scholars, much more significant in the core unanimous finding of the Court is that:
the constitutionally permissible period of executive detention of an alien who has failed to obtain permission to remain in Australia as coming to an end when there is no real prospect of removal of the alien from Australia becoming practicable in the reasonably foreseeable future follows directly from the principle in Lim. 
It followed from this finding that Al-Kateb should be overruled, and the plaintiff should be immediately released from the now unlawful immigration detention. The Court did note, though, that such release is not to be equated with a grant of a right to remain in Australia.
While the decision in NZYQ may have been a long time coming, the orders were delivered with a haste that appears to have taken nearly everyone by surprise. Following two days of hearings, a short adjournment was taken by the Court at 4:17pm. The justices returned at 4:33pm and the newly installed Chief Justice Stephen Gageler informed a disbelieving court that ‘at least a majority’ of justices agreed that sections of the Migration Act could not constitutionally apply to NZYQ.
The Government was caught flat-footed. The plaintiff was immediately released on ‘a visa arrangement with strict conditions’, while a scramble ensued to determine how many other people may be affected by the decision. The latest reporting is that nearly 150 people have now been released.
A frenzied media response has been whipped up by an Opposition campaign of ‘sheer political brutality’. The Labor Government, perhaps spooked by the ghosts of elections past, has sought to engage in a muscular contest with the Opposition over who can be tougher in immigration. That the affected persons are largely convicted criminals has meant there is little public sympathy for the protection of their rights. An eager media has reported as first two, now five former detainees have been subsequently arrested for various offences.
This febrile political context has meant that Parliament has rushed to enact legislative responses to the High Court decision, even prior to the publication of the Court’s reasons. In the month since the orders were announced, two Bills have been introduced and passed through Parliament. The first Act, introducing new bridging visa conditions, was rushed through Parliament on 17 November in an extraordinary 12 hour period from introduction to enactment. This haste has been described as a ‘dark day’ for our democracy. The second Bill was introduced on 27 November, and passed by Parliament on 6 December. This Bill will create a system allowing for the judicially ordered preventative detention of certain former detainees. Whether these responses stand up to judicial scrutiny remains to be seen, with at least one challenge to them already filed. What is clear, however, is that the ‘criminalisation of non-citizens’, as evident in these responses, reflects an ‘alarming acceleration of Australia’s increasingly punitive approach to migration.’
For international readers, mercifully removed from the minutiae Australian politics, the decision is significant for two reasons.
Firstly, Australia has long been an ‘innovator’ in terms of immigration policy. For example, the UK’s recent Rwanda deportation policy was directly inspired by Australia’s 20 year experience of ‘offshore processing’ policies. In a global ‘race to the bottom’, as each country tries to make themselves an unpalatable destination for asylum seekers, the holding that Australia’s indefinite detention is indeed unlawfully punitive may empower other courts to reach similar conclusions. Of course, the current experiments by the Australian government to find constitutional work arounds may just be the next form of draconian immigration innovation to be exported. Have no doubt: Immigration departments around the world will be watching.
Secondly, the substance, form and mode of the High Court’s decision suggest that with Gageler CJ’s elevation and a different mix of judges on the Court, we are seeing a dramatic new phase in the life of Australia’s apex court. Already significant changes have been introduced to special leave procedures, and the Court has returned to visiting regional cities on circuit. NZYQ and other recent judgments appear to signal a bolder, more assertive court than has been seen for decades. Whether this sees the Court emerge from its isolationist phase remains to be seen, but the winds of change are blowing in Canberra.