Top legal experts have given cautious backing to the constitutionality of the Abbott government's latest proposal to strip dual national terrorists of their citizenship.
The government is understood to have largely ditched previous plans to give Immigration Minister Peter Dutton the power to revoke citizenship, which were roundly attacked by many top lawyers.
Instead it is expected to expand an existing law that automatically cancels the citizenship – subject to judicial review – of dual nationals who fight with foreign militaries against Australia, under plans to be unveiled to Coalition MPs in a party room meeting on Tuesday.
Critically the compromise is much more likely to win Labor's backing and restore bipartisanship after a fortnight in which national security became the subject of a political slanging match. Labor has previously expressed in-principle support for such an approach.
The proposal, which is also expected to assuage concerns of Coalition figures such as Malcolm Turnbull, is tipped to extend section 35 of the Citizenship Act to non-state groups such as the Islamic State.
Greg Craven, vice-chancellor of the Australian Catholic University who strongly attacked the government's previous proposal, said that the new option was much less likely to fall foul of the High Court.
"You'd have to see the draft but, on the face of it, if it's a careful draft and they don't do anything silly, it should work," he said.
The major issue with the previous proposal was that it gave powers to the minister that should be only wielded by courts, making it unconstitutional, he said.
Section 35, however, works automatically - the law itself strips the citizenship from the person deemed to have fought with a foreign military or, under the proposed extension, a terrorist group.
Problems would arise if the law limited the scope of judicial review or gave too much power to the minister to decide whether or not someone was a terrorist, Professor Craven said.
While the minister will have to issue the cancellation, security and intelligence agencies will likely make the call that a person is fighting with a terrorist group against Australia and its interests.
George Williams, a law professor at the University of NSW, also said the proposal was less likely to be struck down by the High Court, though he said he remained "very concerned" about it.
He said he would prefer to see an option where the minister could revoke citizenship only after a criminal conviction.
Don Rothwell, an international law professor at the Australian National University, stressed the new proposal could still be unconstitutional, depending on who determined the loss of citizenship and how the review process worked.
"Will there be a capacity for just an administrative appeal, as has been floated? Or will there be the capacity for an appeal on the merits?" he said. "That goes back to the constitutional question."
Labor leader Bill Shorten branded the latest move a "significant backdown from the Prime Minister". But he reiterated a strong support in principle for revoking citizenship of terrorist fighters without making them stateless.
"Any dual citizen taking arms against Australia should be stripped of their citizenship."
