An Australian court has rejected a challenge to the federal government’s draconian power to prevent most citizens from leaving the country so that they do not bring Covid-19 home.

Australia is alone among developed democracies in preventing its citizens and permanent residents from leaving the country except in “exceptional circumstances” where they can demonstrate a “compelling reason”.

Most Australians have been stranded in their island nation since March 2020 under a government emergency order made under the powerful Biosecurity Act.

Libertarian group LibertyWorks argued before the full bench of the Federal Court in early May that Health Minister Greg Hunt did not have the power to legally enforce the travel ban that has prevented thousands of Australians from attending weddings and funerals, caring for dying relatives and meeting newborn babies.

LibertyWorks lawyer Jason Potts argued that Australians had a right to leave their country under the International Covenant on Civil and Political Rights that Australia had ratified.

But the three judges ruled on Tuesday that submission was based on the “erroneous premise that the right is absolute”.

LibertyWorks’ lawyers also argued such a biosecurity control order could only be imposed on an individual rather than an entire population. The order could only be imposed if that individual had symptoms of a listed human disease, had been exposed to such a disease or had failed to comply with travel requirements.

The judges ruled that that interpretation of the law would frustrate Parliament’s clear intentions when lawmakers created the emergency powers in the Biosecurity Act in 2015.

“It may be accepted that the travel restrictions are harsh. It may also be accepted that they intrude upon individual rights,” the judges said in their ruling. “But Parliament was aware of that.”

Critics of the emergency order argue it is harshest for the 30% of Australians who were born overseas.

The government says tough border controls have played an important part in Australia’s relative success in containing the spread of Covid-19.

Surveys have suggested most Australians support the government’s drastic border controls.

The Australian newspaper published a survey last month that found 73% of respondents said the international border should remain closed until at least the middle of next year.