Vigils are being held outside the offices of senior politicians including the prime minister and opposition leader to mark the fifth anniversary of offshore processing.
When Kevin Rudd seized back the Labor leadership in mid-2013 he made it one of his aims to toughen his party's stance on "stopping the boats", to counter then opposition leader Tony Abbott's mantra.
On July 19 of that year, the prime minister announced Australia had entered into an arrangement with Papua New Guinea.
All boat-arriving asylum seekers would be transferred to PNG for processing and settlement in PNG or a participating regional country.
He later struck a deal with the remote Pacific island nation of Nauru.
Manus Island protesters gather outside the Immigration Department building in Melbourne. Source: AAP
When Mr Abbott toppled Labor at the election two months later the new coalition government continued offshore processing and set up Operation Sovereign Borders.
Since then concerns have been raised about the financial cost, oversight of operations, the health and safety of asylum seekers and refugees in the processing centres and the long-term sustainability of the system.
"We remind politicians from both old parties that these five years has condemned 12 people to early death through violence, medical neglect, and despair," refugee support advocate Pamela Curr said in a statement.
The Refugee Council says more than 3000 children and adults have endured "enormous mental and physical harm", yet the government continues to hail the policy as a success and other countries are seeking to mirror the policy as refugee numbers rise.
Malcolm Turnbull told reporters earlier this week the government had restored control over Australia's borders, after Labor allowed 50,000 unauthorised arrivals and at least 1200 people died on dangerous sea voyages.
"The bottom line is we have got our immigration system working exclusively for Australia - the Australian government controls our borders, once again, and so it's going very well," he said.
