One of the government’s key architects of offshore processing says Australia’s offshore detention centres are “terrible”, don’t deter asylum seekers from boarding boats, and are a corruption of what was recommended to government.

Paris Aristotle, AO and the Victorian Australian of the Year for 2017, was a member of the Expert Panel on Asylum Seekers that proposed Australia restart offshore processing of boat-borne asylum seekers. The proposal was one of 22 recommendations to the Gillard Labor government.

Nauru and Manus Island were both reopened in 2012 and have been plagued by allegations of violence, including murder; sexual predation of men, women and, in particular, children; medical neglect leading to death; high rates of suicide and self-harm; and other human rights abuses.

Speaking in Sydney on Tuesday night as part of the University of New South Wales Grand Challenges series examining the impasse in asylum policy, Aristotle said successive governments had focused only on enforcement of boat turnbacks and mandatory offshore detention, and had failed to implement all of the panel’s recommendations, which advocated Australia creating a regional program for processing asylum claims to reduce the incentive for people to board boats.

“What has been put in place is not what was recommended,” Aristotle said.

“The thing that is absent from this is building the architecture necessary in the region to produce a regional protection framework to stabilise populations, assess people’s claims fairly and in a timely way, and provide decent and durable outcomes for them.”

Aristotle, who established Foundation House for the survivors of torture and trauma, said the camps on Manus and Nauru – now in their fourth year of operation – did not deter people from boarding boats.

“One of the great myths about approaches like this to dealing with asylum seekers is the belief that punitive deterrence measures are an effective way of dealing with these things. Many people in the political sphere and in the wider community actually believe that they’re essential to achieving that outcome. But there’s not a skerrick of evidence to prove that.

“The things most people are fleeing are far worse than even the circumstances we might place people in.”

He said people-smuggling operations could be more easily stopped, not by force, but by irrelevancy.

“Instead of punishing people that have had to resort to taking up [people-smugglers’] services, let’s put an alternative system in place that provides safe pathways for people as opposed to them risking their lives.”

Turning back asylum seeker boats to Indonesia or Sri Lanka was not sustainable, Aristotle said. Thirty-one boats, carrying more than 770 people, have been forcibly turned back since Operation Sovereign Borders was established in 2013.

“But if you imagine that one of the countries close to us in the region – if there was a major crisis in Indonesia, Bangladesh, Papua New Guinea – there’s no amount of turnbacks that’s going to work in that scenario.”

Aristotle said Australia’s immigration detention regime was proven to be damaging to those held within it.

“The detention centres are terrible, I’ve been opposed to indefinite mandatory detention for years, the impact is awful for people, but really what crushes people is an absence of hope and an absence of connection.”

Professor Guy Goodwin-Gill, director of UNSW’s Kaldor Centre for International Refugee Law, told the Breaking the Deadlock panel that Australia could not hope to address a global issue with unilateral policies, and that its current suite of policies was not envied or coveted by other countries. It had not “added to the sum of protection” around the world.

“The Australian model is not, as we are sometimes told, an exportable one, it is not viewed with admiration, apart from by some quirky elements on the extremes.”

Goodwin-Gill said the worldwide debate around forced migration needed to hear from those at its centre – the migrants themselves: “Do not speak about us, without us,” last year’s global compact on migration conference was told.

Huy Truong, founding director of Thrive Refugee Enterprise and a former refugee who arrived in Australia by boat in 1978, said the public and political narrative around refugees in Australia needed to change “from being purely a cost and a threat to one of an economic opportunity for Australia”.

Truong said Australia’s nation-building efforts post-second world war had transformed the country.

“We became economically stronger, we became more secure, but we also became a much more just and socially aware country.

“Now, is there a way we can recast our current challenges where when, we look at 65 million displaced people … that there’s an opportunity for Australia to effectively tap into another global talent pool that can lead to the next evolution of Australia?”

The former president of the Australian Human Rights Commission, Gillian Triggs, said Australia had suffered “dreadful leadership” since 2001 on the issue of asylum, and the current policies were unnecessary and had been “one of our lowest points as a nation”.

She said there was “not a scintilla evidence” that holding people in indefinite detention helped stop boats or saved lives at sea.

“We can preserve national security, we can protect our boundaries as a sovereign nation which we’re fully entitled to do, but we can do it in a way which is compassionate, humane, meets our Australian ideals, and, importantly ... meets our international legal obligations.

“We are stopping the boats because we have a military force which has effectively achieved that outcome.”

Triggs said 87% of the refugees in Australia’s region were from Myanmar so increased assistance to that country “looking at the causes of conflict, persecution and poverty” would reduce the forced migration across the region.

Australia is one of Myanmar’s largest aid donors, and resettles significant numbers of refugees from camps on the Thai-Myanmar border.