It is hard to take seriously those Australian politicians who profess concern at mental ill health when they cause so much of it.

Our leaders have created such anguish among those begging for asylum as to drive some desperate refugees to swallow toilet cleaner. For them, suicide is preferable to indefinite detention in Australia's gulags.

At the prison camp in our client state, Nauru, a piece of phosphate once called Pleasant Island, there were 188 recorded incidents of self-harm in the year to July, according to documents obtained under freedom of information by the Herald. There are only 537 people held there.

One man wrapped himself in toilet paper before seeking a lighter. Another leapt from a top bunk with a sheet around his neck. Others tried swallowing lice treatment, insect repellent, anti-dandruff shampoo.

The anguish continues for those in immigration jails on Australian soil. At Villawood, the name of a good Sydney suburb is sullied by such detention centre trauma that one tortured soul's exit strategy was washing down heart medication with half a litre of disinfectant.

All of this is on our watch. Australians own this permanent, indiscriminate cruelty, after repeatedly endorsing mandatory detention since the Keating government introduced it in 1992 as "an interim measure".

Self-harm may not be the policy's clear and deliberate aim, but it is an entirely foreseeable consequence. What else would flow from such inhumane treatment of those who flee their homelands and risk their lives to ask for our help.

Immigration detention is supposed to be bad; it's designed to discourage people from seeking refuge or from overstaying their visas. We lock people up for committing no crime to dissuade others from committing the same non-crime: pleading for asylum.

Our politicians sell it to Australians as the price that must be paid for "protecting" our borders. There have been too many reports for us not to clearly know that that price includes suicide, and an horrific array of methods people attempt to end their detention by ending their lives.

What we do to asylum seekers is one of the two great stains on the reputation of an otherwise great nation: we have yet to properly reconcile with our appalling treatment of Indigenous Australians, and we do great harm to those who seek our protection.

On average, those in immigration detention are imprisoned for more than a year. Under the Turnbull government, the time people spend in detention has rapidly increased, up to an average of 445 days each. That's on average, and many face much longer waits. About a quarter of people in detention have been there for more than 750 days – two years, with change.

Those who have the misfortune of being forcibly taken by Australia to Nauru and found to be genuine refugees are effectively stuck.

The farce of the "open centre arrangements" policy allows them out of the prison camp, and into the rest of the third smallest state on Earth, just behind Monaco, except without the money or multiple exits.

They can visit the remainder of 21 square kilometres of isolated rock, much of which has been destroyed by mining, and revel in an economy smaller than that of the Falkland Islands. That is the limit of their foreseeable future.

The chances of major policy change from either major party is virtually nil. This is an area of government about which our leaders have no shame. The wrongful treatment of Save the Children workers by Scott Morrison when he was immigration minister shows us that, as does the refusal of Peter Dutton to apologise to Greens senator Sarah Hanson-Young. It was reported that she wasput under surveillance while visiting Nauru. Dutton called the report "complete nonsense" and her "an embarrassment to our country".

Except it was completely true, but in his shameless way, he has yet to apologise for the slur. The chances of him apologising for the harm mandatory detention causes to people are nil, despite his declared concern for mental health.

The Immigration Department assures us that those who commit self-harm "are immediately provided with both counselling and medical services" which in "both Nauru and Papua New Guinea are broadly comparable with health services available within the Australian community".

All well and good, but we would hardly need to be paying for mental health treatment for the damage caused while refugees are detained if we didn't detain them. It's less ambulance at the bottom of the cliff, than arsonist wanting a medal for putting the fire out.

Tim Dick is a Sydney lawyer. Twitter: dick_tim

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