CANBERRA – Ten asylum seekers have launched a High Court challenge to the legality of the Australin Federal Government’s offshore detention system.

The asylum seekers come from a variety of countries and are being held offshore but are currently receiving medical treatment in Australia.

The challenge, being run by Melbourne’s Human Rights Law Centre on the asylum seekers’ behalf, will test whether Australian law allows the Government to hold asylum seekers on Nauru and Papua New Guinea.

“The Government needs clear legislative authority to detain people,” said the Human Rights Law Centre’s Daniel Webb.

“One of the key questions at the heart of this case is whether any such authority exists under Australian law.”

The case will argue that because the Government has issued the contracts for the establishment and maintenance of the processing facilities, they are Australia’s responsibility, not that of Nauru and PNG.

It will also argue that necessary laws have not been past to authorise the facilities.

Also of key importance is the $1.2 billion the Government pays to contracted companies to run the facilities.

“It is a truly extraordinary thing for the Government to be spending billions of dollars indefinitely detaining people in other countries,” Webb said.

He said the recent High Court decision in the school chaplaincy case ruled that with limited exception, the Government needs legislative authority to spend public money on big policy issues, but no law had been passed authorising the expenditure on Nauru and Manus Island.

But Professor George Williams from the University of New South Wales said it would be a difficult argument to mount when it came to offshore processing.

“Because even though the Commonwealth will be put to the test, they will need to show that there is responsibility in the constitution over these matters,” Professor Williams said.

“It’s quite likely that they’ll be able to show that. The Commonwealth has a power over alien immigration and its also got a broad power of external affairs which enables it to take responsibility for matter occurring outside of our borders.

“There’s a good chance that the High Court will find that those sorts of areas would enable expenditure on these matters.”

Mary Crock, professor of public law at the University of Sydney, said the case would be of international significance.

“We’ve assumed until now that when we send our refugees overseas that we cut all legal ties with them,” she said.

“It’s not at all clear, however, that this is the case because we are paying for them, and Australia determines who gets released and when.

“So this raises very interesting constitutional, fundamental legal questions about the authority we have in those countries to do what were doing.”

The Government will be asked to give an undertaking not to remove the 10 asylum seekers at the centre of the challenge until the case is decided.

The named respondents in the case are Immigration Minister Peter Dutton, the Department of Immigration and Transfield Services, which manages the processing centres on Nauru and Manus Island for the Government.

Dutton declined to comment on the launch of the case.

One asylum seeker, who cannot be named for legal reasons, is worried about this wife and three-year-old son who are being detained in Nauru.

Speaking through an interpreter, he told the ABC’ she had recently attempted suicide for a second time.

“My wife was never like this. She was a very strong person. I don’t know why she’s doing this, but I can see she is suffering a lot,” the man said.

The man is in Australia on a bridging visa and was reunited with his wife when she was medically evacuated to Australia but was sent back to Nauru after three days.

“I don’t know what she is going to do. I want to be with my wife,” he said.