“The Law Council of Australia suggests that federal and state governments should carefully consider any alternative proposals that would not see people being detained arbitrarily, before introducing post-sentence preventative detention for convicted terrorists,” Mr McConnel said.

Where post-sentence controls are currently in use currently the question of whether someone presents a danger to the community is generally assessed on the basis of medical expertise such as the continued existence of a mental illness, Mr McConnel explained.

“Post-sentence controls are always put before a court, usually the Supreme Court of the relevant state or territory. Final orders are made by a judge exercising his or her discretion,” Mr McConnel said.

“However, it is potentially a very difficult matter to assess whether someone represents a danger to the community because they remain committed to an ideology that would, in their minds, justify a terrorist act.”

Mr McConnel believes that the means by which government would assess whether a person is a danger to the community are likely to be subjective and that the risk of abuse of the power or the wrong application of the power very high.

“The Law Council of Australia would want to be satisfied about how it is proposed such an assessment would be undertaken and against what factors,” he said.

Mr McConnel did admit that recidivism is very high amongst the prison population and that many people who are imprisoned for crimes commit further crimes warranting imprisonment on their release back into the community.

However, he said: “The legal system does not attempt to predict future criminality for most crimes and our criminal justice system generally, with a few notable exceptions, does not permit people to remain imprisoned longer than their term simply because they pose a risk of reoffending.”