Pauline Hanson is pushing ahead with legislation designed to permanently prevent Australians linked to Islamic State and other terrorist organisations from returning home, setting up a major political and constitutional battle over how far Parliament can go in excluding its own citizens.
The One Nation leader’s proposed Protecting Australians from Foreign Terrorist Fighters Bill 2026 would significantly strengthen the legal mechanisms available to deal with Australians accused of joining or supporting terrorist organisations overseas.
Hanson’s proposal includes a new system of foreign terrorist fighter exclusion orders, stronger powers surrounding passports, tougher bail settings for terrorism-related offences and criminal penalties for people who knowingly facilitate the unauthorised return of someone subject to an exclusion order.
Its central and most controversial objective is straightforward: Hanson wants authorities to be able to prevent certain Australian citizens linked to foreign terrorist organisations from returning to the country permanently.
“One Nation will table a bill to permanently block ISIS-linked Australians from coming home,” the party said while promoting the proposal.
But constitutional law experts and the Albanese government say that objective faces a formidable obstacle.
Australia can investigate, arrest, prosecute and impose control measures on citizens suspected or convicted of terrorism offences. It can also temporarily restrict how some citizens return from overseas.
Permanently excluding an Australian citizen from Australia is a very different proposition.
Professor George Williams, a constitutional law and national security expert, has warned Hanson’s proposed permanent exclusion mechanism is unlikely to survive constitutional scrutiny.
Home Affairs Minister Tony Burke has made a similar argument, saying the legislation is unlikely to withstand a High Court challenge.
The dispute is not theoretical.
In recent years the High Court has repeatedly imposed constitutional limits on attempts by the Commonwealth executive to remove Australian citizenship from people accused or convicted of terrorism-related conduct.
That history explains why One Nation has attempted to design its latest proposal around court-issued orders rather than simply giving a minister unilateral power to exclude someone.
The political stakes increased further on Wednesday when the Coalition announced it would support Hanson’s legislation progressing through Parliament.
Senior Coalition figures have indicated they want the proposal scrutinised through a Senate committee process to determine whether it can be made constitutionally robust.
The development creates an unusual alignment between the Coalition and One Nation on national security, even as senior Coalition figures continue to present Hanson’s party as a political competitor.
For Hanson, the policy responds to renewed public attention on Australians who travelled to Syria during the rise of Islamic State and have subsequently sought to return.
The issue became particularly prominent again in May when several ISIS-linked Australian women returned from Syria.
Three women were arrested after arriving in Sydney and Melbourne.
One woman was charged over allegations including entering and remaining in a declared conflict zone and membership of a terrorist organisation, while two others faced serious charges following their arrival.
The arrests demonstrated one of the central arguments made by the Albanese government: allowing an Australian citizen to return does not mean authorities are powerless to act against that person.
Australian law contains an extensive range of terrorism and foreign-incursion offences, and suspects can be arrested and prosecuted when admissible evidence supports charges.
Hanson argues prosecution after arrival is not sufficient in the most serious cases.
Her position is that Australians who voluntarily joined or materially supported organisations such as Islamic State should not be entitled to rely on their Australian citizenship to return after participating in or supporting a terrorist movement overseas.
The legal difficulty is that citizenship carries consequences extending beyond possession of an Australian passport.
An Australian passport is a travel document. Australian citizenship is a legal status.
Cancelling or refusing a passport may make international travel much more difficult, but it does not necessarily extinguish a citizen’s underlying entitlement to enter Australia.
That distinction is central to the constitutional debate surrounding Hanson’s proposal.
Australia already has a Temporary Exclusion Order regime, introduced in 2019, designed to manage the return of Australians of counter-terrorism interest.
Temporary exclusion orders can prevent a person from returning to Australia for a limited period without a return permit.
The system allows authorities time to prepare for the individual’s arrival and impose conditions intended to manage the security risk.
Those conditions can regulate matters such as when and how the person returns.
The regime was deliberately constructed around temporary exclusion rather than permanent banishment.
That difference could prove decisive.
One Nation argues temporary arrangements are inadequate for people who have demonstrated allegiance to an overseas terrorist organisation.
Its bill seeks to establish a stronger foreign terrorist fighter exclusion order issued through the courts.
Using a court rather than a minister is an important feature because of the constitutional problems encountered by previous citizenship-stripping laws.
In 2022, the High Court delivered its decision in Alexander v Minister for Home Affairs.
The case involved an Australian-born dual citizen whose Australian citizenship had been removed by the home affairs minister after the government concluded he had engaged in conduct connected with terrorism overseas.
By a six-to-one majority, the High Court held the relevant provision of the Australian Citizenship Act invalid.
A central problem was that the law effectively allowed the executive government to impose the serious consequence of citizenship deprivation on the basis of conduct it determined had occurred.
The court concluded the provision involved an exercise of judicial power that could not constitutionally be given to the minister.
The Commonwealth subsequently encountered another major defeat in Benbrika v Minister for Home Affairs in 2023.
That case involved convicted terrorist Abdul Nacer Benbrika, whose Australian citizenship had been cancelled under a separate provision.
The High Court again found the citizenship cessation mechanism constitutionally invalid.
Those decisions forced the Commonwealth to redesign its approach.
Current citizenship cessation law now gives the minister the ability to apply to a court for an order terminating citizenship in specified circumstances rather than simply imposing that consequence through an executive decision.
Home Affairs confirms that section 36D of the Australian Citizenship Act permits the minister to apply to a court for a citizenship cessation order.
That history helps explain One Nation’s emphasis on presenting its proposal as “court-proof”.
The party is attempting to avoid the constitutional defect identified in earlier laws by placing the decisive exclusion power with a court.
But that does not necessarily resolve the deeper problem.
The question is not simply who makes the order.
Constitutional scrutiny may also turn on whether Parliament has power to permanently exclude a person who remains an Australian citizen from the Australian community.
That is why legal experts remain sceptical even though Hanson’s proposed mechanism involves the Federal Court.
The debate therefore reaches into a fundamental question about citizenship: can someone remain legally Australian while simultaneously being permanently forbidden from entering Australia?
Hanson’s political answer is that national security should prevail where a person has associated themselves with a terrorist organisation hostile to Australia.
Critics argue citizenship cannot be reduced to a privilege that Parliament can effectively suspend indefinitely while technically leaving the legal status intact.
There are also practical questions about how an exclusion order would operate.
A person prevented from entering Australia must remain somewhere else.
If that person is solely an Australian citizen, another country may have no obligation to accept them indefinitely.
The problem becomes different for dual nationals because another country of citizenship may provide a lawful place of residence, although citizenship deprivation in such circumstances remains constrained by Australian constitutional law.
International obligations can create additional complexity, particularly where people are detained in unstable regions or where children are involved.
The political debate often groups several very different categories of people under labels such as “ISIS fighters”, “ISIS brides” and “supporters”.
Legally, those descriptions are not interchangeable.
A person who fought for Islamic State, a person who formally joined the organisation, a spouse who travelled into territory controlled by it and a child taken overseas by a parent can present dramatically different factual and legal circumstances.
Australian authorities still need evidence capable of establishing the conduct attributed to each individual.
That distinction is particularly important for children born or raised in Syrian camps, some of whom had no role in their parents’ decisions.
Hanson’s legislation is principally framed around people linked to foreign terrorist organisations rather than treating children as responsible for their parents’ alleged conduct.
The renewed debate follows years of uncertainty surrounding Australians detained in camps in north-east Syria after the territorial collapse of Islamic State.
Some Australians remained there for more than seven years before making their way home.
When a group of ISIS-linked women returned in May, Australian authorities were waiting.
Three were arrested following their arrival, demonstrating that return and criminal accountability are not mutually exclusive.
That is central to Labor’s approach.
The government argues Australians suspected of committing terrorism offences should face Australian law rather than simply being left indefinitely overseas.
Authorities can investigate alleged conduct, impose appropriate security measures and prosecute where evidence permits.
Burke has also warned that attempting to establish an unconstitutional permanent exclusion system could create unintended consequences for other government priorities.
The Home Affairs Minister has linked the debate to Australia’s ability to remove hundreds of non-citizen criminals from the country, arguing that careless changes to the legal distinction between citizens and aliens could undermine other aspects of migration law.
One Nation rejects the suggestion that constitutional difficulty should end the discussion.
Hanson’s argument is effectively that if existing legislation is inadequate, Parliament should attempt to construct stronger legislation within constitutional limits rather than accept the status quo.
The Coalition is now taking a similar procedural position.
Rather than dismissing Hanson’s proposal outright, it wants the bill examined and tested through the parliamentary process.
Shadow ministers have argued national security warrants cooperation with One Nation where the parties share common ground.
The bill’s prospects nevertheless remain uncertain.
Coalition support can help it progress in the Senate, but government cooperation would be required for the proposal to advance through the House of Representatives.
Labor has given no indication it intends to provide that support.
The constitutional warning is likely to be central to the government’s opposition.
There is also a broader policy disagreement over what Australia should do with citizens accused of serious conduct overseas.
Permanent exclusion has obvious political appeal.
It promises to keep a perceived threat physically outside Australia and avoids the prospect of people associated with a notorious terrorist organisation living in Australian communities.
But keeping a citizen overseas does not necessarily eliminate the threat.
Security experts have long debated whether controlled return, surveillance and prosecution can sometimes provide governments with greater ability to manage dangerous individuals than leaving them in unstable foreign jurisdictions.
Former Home Affairs secretary Mike Pezzullo has suggested there may be merit in a compromise approach that makes stronger use of temporary exclusion arrangements while ensuring authorities control the circumstances of a person’s eventual return.
Such an approach would sit between Labor’s existing framework and Hanson’s proposed permanent ban.
It would recognise that some returnees may pose serious security risks while avoiding the unresolved constitutional question of permanently excluding an Australian citizen.
The ultimate policy choice involves several competing principles.
Governments have an unquestioned responsibility to protect Australians from terrorism.
They also operate within a constitutional system in which Parliament and ministers do not possess unlimited power simply because national security is invoked.
The High Court’s citizenship decisions are a powerful reminder of that constraint.
In Alexander, the seriousness of the allegations did not save legislation the court concluded improperly vested punitive power in the executive.
The lesson for Hanson’s bill is that strong political support for excluding terrorist suspects does not answer the constitutional question.
Nor does the constitutional problem mean Australia must simply allow a suspected foreign fighter to walk through an airport without consequence.
Existing law permits temporary exclusion and controlled return, while terrorism offences can carry severe criminal penalties when prosecutors establish the required evidence.
Citizenship cessation can also still be pursued in limited circumstances through a court-based process established after the High Court’s earlier decisions.
The real dispute is therefore over the gap between those powers and the permanent exclusion Hanson wants.
One Nation says that gap leaves Australians unnecessarily exposed.
Labor says attempting to fill it with a permanent ban on citizens returning would probably produce legislation that fails in the High Court.
The Coalition now wants Parliament to test whether Hanson’s proposal can be modified into something constitutionally sustainable.
That ensures the debate will not be confined to the fate of a relatively small number of Australians linked to Islamic State.
It will also become a test of the boundaries of Australian citizenship itself.
Parliament can make terrorism offences, prosecute offenders, restrict passports and regulate the return of people considered security risks.
What it may not be able to do is declare that a person remains an Australian citizen in name while permanently closing Australia’s border to them.
Hanson wants Parliament to find out exactly where that constitutional line lies.
