The outbreak of disunity in Labor came after the Papua New Guinea Supreme Court ruled the Manus Island detention centre was illegal and unconstitutional, and PNG Prime Minister Peter O'Neill said it would be closed. "We have caused them enough suffering already": Labor MP Melissa Parke. The ruling has thrust asylum seeker policy squarely back onto the political agenda on the eve of the federal election campaign. It is not yet clear when the Manus Island facility could shut, nor where the asylum seekers will be processed if they are forced to leave PNG. Labor's official policy is to support the offshore processing of would-be asylum seekers and to support the turning back of asylum seeker boats attempting to come to Australia. That policy was formally adopted at the party's annual conference in 2015, over the objections of a minority of vocal opponents, primarily in the party's Left faction. Labor MPs Melissa Parke, Lisa Singh, Jill Hall and Sue Lines told Fairfax Media the court ruling was a chance for the opposition to re-think its policy on offshore processing and bring the asylum seekers to Australia.

"It's inevitable that the government will need to have another plan for what is going to happen, and the most logical thing to do is to bring those people to Australia," said Ms Parke, who is a former UN lawyer and advocate for asylum seekers and is set to retire from Parliament. Tasmania Senator Lisa Singh says the Pontville detention centre north of Hobart should be re-opened to process the asylum seekers. Credit:Alastair Bett "We have caused them enough suffering already. This is a sick game and it needs to end." Senator Singh, a junior member of Mr Shorten's frontbench who is based in Tasmania, said the Pontville detention centre north of Hobart should be reopened to process the asylum seekers in limbo on Manus Island. Opposition Leader Bill Shorten says Labor supports regional processing in offshore facilities. Credit:Alex Ellinghausen

"I think Tasmania could play a really active role in the resettlement of these refugees and asylum seekers who are likely to be displaced from Manus Island," she said. "Pontville has a reputation as a humane and preferable option. I think bring them here and process them, definitely. It needs some rehabilitation, but it could temporarily house them in the next couple of weeks, those on Manus island." Ms Hall, who is also retiring, warned that "history will judge Australia very poorly" for its treatment of asylum seekers, and said she had "always been supportive of onshore processing." Asked if the asylum seekers on PNG should be brought to Australia, Ms Hall said: "Australia has a responsibility to them; we can't throw our hands up in the air. I don't think we have fulfilled that responsibility in the way we should have with the people who are on Manus." Chance for a rethink

Senator Lines said the PNG Supreme Court's decision was "a chance for a rethink on offshore processing". Mr Dutton said it was clear that Labor's promise to process asylum seekers offshore was already unravelling. "At least in the run-up to the 2007 election Kevin Rudd was able to hold his team together until they got into government before they dumped the policies that had stopped the boats," he said. But Mr Shorten said on Thursday Labor had debated the issue of offshore processing last year and "we haven't shirked any of these issues", though he avoided questions about the split in his party's ranks. Labor and the Liberals were on a "unity ticket to defeat the people smugglers," he said. "There isn't a single person in Labor who wants to see the boats start again or wants to see indefinite detention."