Admiral Chris Barrie at the change of command ceremony in 2002. Credit:Andrew Taylor The admiral was chief of the Australian Defence Force between 1998 and 2002. He prepared and oversaw the Howard government's Operation Relex, launched following the Tampa affair and which eventually dealt with several thousand asylum seekers during those years. Admiral Barrie said the demonising of asylum seekers in Australia's detention centres was a central concern for him. "I'm not sure we should continue to use the term 'mandatory detention' when we actually mean jail," he said. "At least in Australian jails the incarcerated have rights of access to legal support and representation. In these jails no such rights exist."

Two asylum seekers, one with an eye injury, leave Manus Island airport following the detention centre violence in which Reza Barati was killed earlier this year. Credit: Nick Moir He also accused the department of "double handling" by sending asylum seekers back to Iraq and Syria, and said Immigration Minister Scott Morrison had acknowledged the humanitarian crisis in those countries by setting aside 4400 resettlement places from the war-torn region. Mr Morrison responded to Admiral Barrie's comments late on Thursday. "Admiral Chris Barrie has been a consistent critic of the policies that have proven to be so successful. He is entitled to his view but I must respectfully disagree again with his comments," he said. Criticism of the government's asylum-seeker approach comes amid claims an asylum seeker who contracted severe septicaemia and is now "brain dead" was subject to delays in his initial treatment.

Admiral Barrie has dealt with his share of immigration controversy – he was chief of the defence force during the Children Overboard affair in 2001. At the time, he initially supported government claims that children had been thrown overboard but subsequently recanted, saying there was no evidence to support them. He has been a vocal critic of the tow-back policy, saying it has put naval personnel at risk. Last December, he said if the Coalition's tow-back policy was implemented, boats would be burnt and sunk and people would end up in the water. Admiral Barrie was launching a book by international law academics Jane McAdam and Fiona Chong, Refugees: Why Seeking Asylum is Legal and Australia's Policies are Not. The book asserts that Australia's policies towards asylum seekers are illegal under international law. It details the "international dismay and bewilderment at Australia's treatment of asylum seekers," author Professor McAdam said.

"This is doing a lot of damage to Australia's reputation as a good international citizen." She criticised the government for having double standards when it came to international law. "The Foreign Minister, Julie Bishop, said 'Australia cannot have an island mentality,' in relation to international trade and investment. This is a sentiment that should be applied to a refugee context as well." Admiral Barrie was also scathing of the Immigration Department's secrecy surrounding border operations. "Running this in secret does not stack up. We stopped the boats in 2001 without the need for any of it," he said.

He also criticised the cost of Operation Sovereign Borders. "The current mechanisms for managing asylum seekers does seem to me to be outrageously expensive for a country that was built on immigration." Last month, Fairfax Media reported that the federal government's failed attempt to return 157 asylum seekers to India cost taxpayers more than $12 million. Loading The Immigration Minister has defended the government's asylum-seeker policy, saying it is necessary to prevent deaths at sea, of which there have been more than 1500.