With millions of people in Australia confined within state lines - and some within 5km of their home - uptake of the COVID-19 vaccines are soaring with the promise of an end to travel restrictions once thresholds are reached.
But experts say the 80 per cent national vaccination target alone may not herald the end of state border closures.
Is it likely states would keep their borders closed?
COVID-19 advisor to the World Health Organisation, UNSW professor Mary-Louise McLaws, says it’s highly likely the states may continue to restrict interstate movement.
“If there’s no self-testing, no internal border testing, then yes, we will see borders shut down, closed, and that’s going to create a lot of problems.”
A police officer stops a driver at a checkpoint at Coolangatta on the Queensland-New South Wales border. Source: AAP
Nationally, 36 per cent of adults in Australia are fully vaccinated and 60 per cent have received one dose.
How have legal challenges gone in the past?
Legal challenges to state border restrictions so far have been unsuccessful.
The most high profile - that of mining magnate Clive Palmer early last year - argued in the High Court that closing borders was in breach of the constitution.
Associate Professor at the ANU College of Law Amelia Simpson says while the case was unsuccessful, future challenges may go further as the pandemic stretches on.
Clive Palmer challenged the WA border closure in 2020. Source: Getty Images AsiaPac
“In terms of the High Court’s readiness to question what governments were doing in and around their responses to COVID-19, I think it was a bit early to ask the court to do something as dramatic as ask a state to open its borders when it is not willing.”
What does Australia's constitution say?
The two sections of the constitution raised in relation to objections against state border closures are section 92 and section 117.
Section 92 states: "On the imposition of uniform duties of customs, trade, commerce, and intercourse among the States, whether by means of internal carriage or ocean navigation, shall be absolutely free”.
Intercourse refers to the movement of people between states.
Section 117 states: "A subject of the Queen, resident in any State, shall not be subject in any other State to any disability or discrimination which would not be equally applicable to him if he were a subject of the Queen resident in such other State”.
But constitutional law expert at the University of Sydney Professor Anne Twomey says neither are absolute, as historically the High Court has recognised states can impede movement if reasonable and necessary for public safety.
“It’s always been the case that absolutely free could not always mean absolutely free. There has to be some restrictions on it in order to do things like protect public health. We have early cases from the 1920s and 1930s dealing with it.”
Haven't the states agreed to the 80 per cent plan?
Under the federal government's four-phase plan to reopen Australia, lockdowns will become less likely at the 70 per cent vaccination mark, with only targeted lockdowns to be used after 80 per cent of those aged over 16 are fully vaccinated.
While all states and territories agreed to the plan, several states have since indicated they may not be ready to reopen borders once national vaccine thresholds are reached.
People queue at a COVID-19 vaccination centre in Melbourne. Source: AFP/Getty Images
Associate Professor Simpson says this raises the prospect of future High Court challenges as the argument to supersede the constitution loses traction.
She says as time stretches on and more of the population is vaccinated, the High Court will have to weigh up the necessity and reason for a lockdown, against its economic, psychological and associated impacts.
“There’s going to come a time when that reasonableness equations shifts significantly and I don’t think anybody, not even the premiers of the states that are being called hermits in the media, will want these situations to go on indefinitely.”
Can the federal government overrule the states?
Professor Twomey says in theory the federal government could overrule state border restrictions by passing all-encompassing national legislation governing movement during a pandemic. But so far it’s chosen not to.
“The Commonwealth’s chosen not to take that course. It’s left it to the states as a public health response and the consequence is the states are able to put up these restrictions.”
Professor McLaws says border closures and ring-fencing has been largely successful in containing the virus in Australia thus far. But, she says, the outbreak of the Delta variant has changed the game, and now the state governments must change the rules.
Source: Getty Images Europe
“We have Delta now and we’ve got to learn to work to reducing risk because getting Delta down to zero is nigh on impossible.”
She says rapid antigen self-testing, commonly used in countries including the UK, will be key to life out of lockdown in Australia.
