Almost half of the asylum seeker children returned to Australia from Nauru’s detention centre – the public focus of the Let Them Stay campaign – have been diagnosed with a mental illness, the government has told parliament.

Fifty-four children returned to Australia from Nauru were part of the 267 asylum seekers and refugees who were the focus of a nationwide Let Them Stay campaign.

In answer to a February question on notice specifically about that 267 cohort, a Department of Immigration and Border Protection official has told the Senate: “as at 8 February 2016, there were 25 minors from Nauru who were in Australia with a clinically diagnosed mental health condition including depression and anxiety”.

“Additionally, there were five minors in Australia for other long-term medical issues.”

In February, 267 asylum seekers and refugees became the focus of intense public campaigning over a high court challenge to their detention and government plans to return them to Nauru and Manus Island.

The 267 had been brought to Australia from the detention centres on Nauru and Manus Island because of a serious medical condition, or because a close family member required medical attention.

Thirty-seven were babies who had been born in Australia, and had never been to Nauru, but were deemed “illegal maritime arrivals” because of their parents’ migration status.

Fifty-four were children who had been detained in the Nauru detention centre. Guardian Australia understands there may be a small number of additional children returned to Australia from Nauru who are not part of the 267.

The government’s own reporting has found detention is especially harmful for children.

The chief medical officer and surgeon general of the Australian Border Force, Dr John Brayley, told a Senate estimates hearing in February: “the scientific evidence is that detention affects the mental state of children, it’s deleterious.”



“Wherever possible, children should not be in detention.”

Confidential reports to government by detention health provider IHMS – obtained under Freedom of Information by the Guardian – consistently show children in detention suffer more acute mental health crises than adults, and their mental health deteriorates the longer they are detained.

IHMS has also told the government mental health damage to children persists long after they are released.

Greens Senator Sarah Hanson-Young, who asked about the children’s mental health at the Senate estimates hearing, said the children and their families should be allowed to apply for permanent visas to stay in Australia “so that they can live in safety and rebuild their shattered lives”.



“Threatening to send these children to Nauru is keeping them in a state of constant fear and anxiety,” Hanson-Young said. “No child should be subjected to this sort of mental torture.”

The 267 asylum seekers were enjoined to a high court challenge brought by a Bangladeshi women – M68 – who challenged the constitutionality of her detention offshore.

The M68 challenge failed in the high court, a majority of the full bench ruling the government does have the power to detain people offshore.

But as public protests grew across the country under the banner of Let Them Stay, and more than 100 churches said they would defy the government to offer sanctuary to those facing removal, the 267 were allowed to stay in Australia.

None have yet been returned to Nauru or Manus. More than half, including all of the children, have been released from immigration detention into the Australian community.

The government maintains there has been no alteration to the policy of offshore processing that, it says, demonstrably saves lives at sea.

Immigration minister Peter Dutton said the 267 are liable to be returned to Nauru or Manus because there is “no lawful basis” for them to stay in Australia.

He said children would not be sent “back into harm’s way,” but that the government would maintain “the principle we’ve adhered to in the past”, that people needing serious medical treatment would be brought to Australia as required, but would never be resettled in Australia.

“When there’s no longer a case for them to remain in Australia, they will be returned.”

Shen Narayanasamy, human rights director of GetUp!, the organisation which led the Let Them Stay campaign, said medical opinion had conclusively shown detention camps caused mental and physical harm to those detained.

“It is shocking, but unsurprising, that so many of the 267 children are suffering, and [this] should prompt the government to let them stay in Australia.”

She said the children in the 267 cohort still suffered because of the uncertainty around their futures.

“With the government still stating that they will be deported, they can’t even plan to be here for a football final. This uncertainty is extremely damaging for anyone, let alone a child.”

Daniel Webb from the Human Rights Law Centre said it was inexcusable that successive governments had knowingly caused harm to children by detaining them.

“Some of these children actually took their first steps and spoke their first words in detention and until recently had never known a day of freedom in their lives. Finally releasing them was an important first step towards compassion and decency.



“The next step is to allow them to apply for protection in Australia. They need to be able to begin rebuilding their lives without the threat of sudden deportation hanging over their heads.”

Webb said adults were harmed by detention too. “It doesn’t suddenly stop damaging people on their 18th birthday”.

The government announced earlier this month it had released all children from detention, moving families into community detention. For some children, this was done by reclassifying the family compound of Villawood detention centre as “community detention” and relaxing monitoring. Some children, who were not boat arrivals and were facing removal from the country, were still detained beyond the government’s declaration.

And Australia’s policy of mandatory detention of all boat arrivals, including children – in effect since 1992 – remains unchanged.

Fifty children remain on Nauru. Both the Australian and Nauru governments maintain those children are not detained because the camp is now an “open centre”. This is contested by refugee advocates, human rights groups and lawyers.

Also revealed by Senate estimates questioning:

