Pawel Francuziak came to Australia from Poland in 2006, two years after being

He had spent only a short time behind bars before coming to Australia, and was on bail and awaiting an appeal.

Eventually, Mr Francuziak's appeal was dismissed, but he could not be found by Polish authorities who were wanting to impose his prison sentence.

Mr Francuziak did not hide his identity in Australia, and spent his time as a full-time pastry cook in Perth, meeting a woman and forming a steady relationship.

He was later arrested and has since spent four years behind bars in Australia awaiting extradition.

The federal government, through Justice Minister Michael Keenan, was then faced with the decision of whether to surrender Mr Francuziak to Poland.

The detainee argued against his extradition, saying Poland could not be trusted to carry out his sentences in accordance with expected standards of humanity.

The system, he said, was marked by serious overcrowding, rampant violence, delays in hearing parole applications, disease, and a lack of medical facilities.

He said he would face beatings from fellow inmates and guards because he was a sex offender, and argued that he would face inhumane and degrading treatment, which amounted to torture.

Mr Francuziak, who maintains his innocence to the crimes, said he had no other criminal history, had not offended in Australia, and had already served more time behind bars than he would have in Poland.

Australia has non-refoulement obligations under the United Nations Convention Against Torture.

But the minister, acting on advice from the Attorney-General's Department, rejected the argument, instead surrendering Mr Francuziak for extradition.

The department had told Mr Keenan he could be satisfied that Mr Francuziak would not be subjected to torture in Poland.

It advised that the ill-treatment of convicted sex offenders was limited to a minority of law enforcement officials in only some prisons.

Mr Francuziak appealed against the minister's decision in the Federal Court, which handed down its decision last week.

He argued that the minister had asked himself the wrong question when deciding on his fate.

The minister's decision, he said, had been based on whether or not the problems with the Polish system were a direct result of deliberate government policy designed to punish and harm inmates.

He said the minister should have asked himself only whether Mr Francuziak would be mistreated, or whether there was a "real chance" of mistreatment occurring, regardless of the intentions of Polish government policy.

Mr Francuziak said the evidence he put to Mr Keenan showed "a consistent pattern of gross, flagrant or mass violations of human rights" in Poland's prisons.

But Justice Neil McKerracher rejected that argument, saying the test was whether there was "institutionalised torture", not occasional and unpredictable violence occurring in prisons.

Justice McKerracher said that issue was properly considered by the department.

Mr Francuziak had also argued that the delays in considering parole, the years he had already served, and his changed circumstances made it unreasonable to extradite him and was totally incompatible with humanitarian considerations.

That argument was also rejected by Justice McKerracher.