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Immigration, Mental Health

Risk of PTSD 20 times higher for people held in offshore detention: study

UNSW Sydney 5 mins read

Researchers at UNSW uncover evidence of the negative psychiatric impacts of Australia’s onshore and offshore detention systems in the largest study of its kind.

 

A study of immigration detention in Australia has shown refugees detained offshore for any amount of time face a 20 times greater risk of PTSD and other mental health problems compared with asylum seekers who were detained onshore for less than six months.

The researchers from UNSW Sydney say the same debilitating effects on mental health were also evident in those who had experienced protracted stays in onshore detention facilities. These impacts were evident years after leaving detention to live in the community.

In a letter to the editor published today in the British Journal of Psychiatry, the researchers detailed their survey of 990 adult refugees and asylum seekers living in the Australian community between 2011 and 2018. This group included 215 individuals who had experienced some form of detention before eventually joining the Australian community.

The researchers say the survey offered “unique insight into the long-term psychological effects of offshore processing”.

Dr Philippa Specker is the lead author of the study and a researcher and clinical psychologist with UNSW’s School of Psychology. She says the study represents the largest known available dataset relating to offshore processing and mental health.

“Because of the legal and logistical barriers to contacting people held in Australia’s offshore detention centres on Manus Island and Nauru since 2012, research can only be conducted with detained people once they’ve been released,” she says.

“This survey data allowed us to test for the first time whether previous experiences of offshore detention impacted someone’s risk of experiencing long-term serious mental illness once living in the community, by comparing them to people who had been detained onshore for less than six months.”

Emphatically, the research found that it did.

“We found that if you had been in onshore detention for longer than six months, or offshore detention for any length of time, your risk of having subsequent PTSD, depression or suicidal ideation was significantly greater, and of a magnitude that really surprised us.

“People were between 17 and 20 times more likely to report PTSD symptoms if they'd spent a long time in onshore detention, or if they'd spent any amount of time in offshore detention.”

Other statistics revealed that people who were detained in any form were twice as likely to have probable PTSD, two and a half times more likely to have probable depression and almost twice as likely to have suicidal ideation, compared to refugees and asylum seekers who never encountered immigration detention. When comparing the experience of offshore and onshore detention of any length, offshore detainees were 2.71 times more likely to have probable PTSD.

The increased mental health risks were evident despite comparing against a control group of refugees and asylum-seekers and despite controlling for age, gender, time in Australia and marital status. This suggests that exposure to detention impacted mental health over and above other important factors.

 

Negative impact

The researchers say it has long been established that onshore detention has destabilising effects on the wellbeing of asylum seekers, but the recent analysis of data shows these negative effects are even greater for offshore detention.

“Being removed to another country by the government that one is applying for asylum from can undermine one’s sense of safety, agency, and certainty about the future. It is understandable then, that such practices might also carry serious and long-term psychological consequences,” Dr Specker says.

“With more than 117 million people forcibly displaced due to war, persecution and human rights violations – and 38 million of these being refugees – there have never been more people displaced in the world due to wars and persecution. At the same time, we’re seeing first-world countries making more and more restrictive immigration policies with the aim of deterrence.”

But Dr Specker says there is now an opportunity to address the problem of displaced people seeking sanctuary with measures that are practical, rather than punitive.

What can be done?

“We understand that when someone's arriving to a new country and they're seeking asylum and lodging an asylum claim, of course, that requires some degree of administrative processing,” Dr Specker says.

“What our findings are telling us is that the way a person is treated while their asylum claim is being processed can make a really big difference.”

The researchers call for a reimagining of asylum seeker policies that rest on the use of detention.

Firstly, they say, the use of offshore detention needs to be re-evaluated. The researchers point out that Australia is one of 145 signatory nations to the United Nations 1951 Refugee Convention, which outlines a humanitarian obligation to provide protection to people fleeing persecution and human rights violations. Given the data suggesting high rates of PTSD, depression and suicidal ideation among people who have experienced offshore detention, a government would be hard pressed to argue such a policy is humanitarian.

“Our findings highlight the psychological costs of offshore detention, and add to wider research that has also revealed other shortcomings in policies of immigration detention and processing,” Dr Specker says.

“For example, analysis of migration patterns has revealed that immigration detention and offshore processing is ineffective in actually deterring people from seeking asylum. Beyond this, the UNSW’s Kaldor Centre for International Refugee Law calculated that holding someone in offshore detention is 5550 times more expensive than allowing them to live in the Australian community while their claim is being processed.”

Secondly, processing asylum claims needs to be timely. The researchers found even worse mental health outcomes among those who spent a longer period in onshore detention, relative to those who were released within six months. Considering that, as of 31 July 2024, the average length of time people were held in onshore detention was 545 days (1.5 years), there is an urgent need to significantly expedite processing times and ensure that people are not detained while their claims are being processed.

 

Lesson to be learned

Researchers point out that this year, the British parliament approved the Rwanda Immigration Bill for offshore detention, which the new Labour government has promised to repeal. With Australia among the few countries practicing offshore immigration detention, researchers hope their recent study will offer timely evidence to other nations on the severe psychiatric impacts of such practices.

“It is not too late for Australia, and other governments seeking to establish similar models of offshore processing and immigration detention, to instead consider evidence-based alternatives,” Dr Specker says.

 

Read the letter: https://doi.org/10.1192/bjp.2024.184

 


Key Facts:
  • refugees detained offshore for any amount of time face a 20 times greater risk of PTSD and other mental health problems compared with asylum seekers who were detained onshore for less than six months.
  • the average length of time people were held in onshore detention in Australia was 545 days (1.5 years)
  • holding someone in offshore detention is 5550 times more expensive than allowing them to live in the Australian community while their claim is being processed
  • people who were detained in any form were twice as likely to have probable PTSD, two and a half times more likely to have probable depression and almost twice as likely to have suicidal ideation, compared to refugees and asylum seekers who never encountered immigration detention.
  • when comparing the experience of offshore and onshore detention of any length, offshore detainees were 2.71 times more likely to have probable PTSD

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