Recent revelations that employees of the company contracted by the Home Office to deport foreign national prisoners and refused asylum seekers have been "loutish" and "aggressive" comes as no surprise. And it's no accident that these groups of people ? the UK's prime pariahs ? should be lumped together as a job lot of untouchables whose fate is easily shrugged off.

The foreign national prisoner as hate figure emerged after former home secretary Charles Clarke was sacked for admitting that 1,000 foreign criminals were released between 1999 and March 2006 without being considered for deportation.

In the wake of this rumpus, Tony Blair tried to set the agenda by saying he wanted the "vast bulk" of foreign prisoners to be automatically deported "irrespective of any claim that they have that the country to which they are going back may not be safe". Under the 2007 UK Borders Act, deportation became automatic for foreign nationals convicted of a crime carrying a sentence of 12 months or more.

At that time one name caught my attention ? Joker Idris, real name Abdullah Hagar Idris. His story couldn't be less that of a Joker. He was a foreign national prisoner who committed suicide in prison in 2007.

An asylum seeker from Darfur, Idris arrived as an unaccompanied minor, escaping after the Janjaweed destroyed his village. His family were scattered. He was alone and feared for his life.

In October 2007, charged with affray, he got a 12-month prison sentence. It was clear from his police custody record that he was mentally disturbed, he had self inflicted cigarette burns on his arms, a cross carved into his flesh and was behaving strangely. He hanged himself in HMP Chelmsford on Christmas Day, aged 18. An inquest found "serious failings" by HMP Chelmsford and Essex social services which contributed to his death. Papers given to him in jail the day before he died revealed that he would be held beyond the term of his sentence, pending deportation.

Shocked by this story, I filed an freedom of information request asking how many foreign national prisoners had died in UK jails since Charles Clarke left office. The FOI request's response from the Ministry of Justice revealed that there were 70 foreign national prisoner deaths between 2007-2010, over half of them ? 44 ? self inflicted, a "significant spike" said the MoJ. Numbers had since returned, they continued, to "expected levels". Were those 44 people, whose names, stories and convictions remain a mystery, so frightened of being returned that suicide was the better option?

Research by Bail for Immigration Detainees (BID) found that foreign national prisoners, contrary to the murderous demon of the public imagination, exhibited 'extreme diversity'. Many had been here for most of their lives. Among Clarke's "missing" miscreants, Anne Owers ? the chief inspector of prisons at the time of the debacle ? found UK citizens, Irish and EU citizens and people who had committed minor offences, had families and were settled here.

Of course, there are foreign nationals in UK jails who are violent criminals and antisocial law breakers for whom one feels no sympathy. But grades of guilt and innocence shouldn't be a measure for how we treat people in custody, nor a justification when they commit suicide or are killed. Jimmy Mubenga, who died while under restraint during deportation by G4S escorts on a British Airways flight, had served a two-year sentence for a violent crime. Nothing justifies his death, nor the suicide of Joker Idris and the 44 prisoners in that "spike" in UK jails.

There is further erosion of these people's human rights in the fine print of the forthcoming legal aid, sentencing and punishment of offenders bill, in two largely unnoticed clauses.

Number 126 introduces a conditional caution for low-level crimes which, if agreed to, means the offender can avoid courts and prisons. The deal is: agree to removal rather than deportation and to exclusion instead of a court hearing, a prison sentence and a criminal record. Sounds reasonable ? but is it? Dr Adeline Trude of BID explains her concerns: "If they were facing deportation they would have a right of appeal, but by merely facing administrative removal they have no right of appeal, and are therefore less protected ? ironically ? than they would be if facing court, conviction, and sentencing."

Clause 132 takes it a step further and erases the notion of spent convictions, so that anyone deported as a foreign national stays deported in perpetuity no matter how minor the conviction. These clauses have wide implications and are typical of the casual, hysterical, confusion and contempt at the heart of policies determining the fates of the UK's latest pariahs.

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