The case was brought on behalf of a plaintiff under the pseudonym of NZYQ,a stateless Rohingya man who lost his Australian visa after being convicted of raping a 10-year-old boy.

The individual’s legal team argued it was unconstitutional for the Commonwealth to hold a person with no prospect of leaving Australia.

Gageler agreed.

“It is declared that,by reason of there having been and continuing to be no real prospect of the removal of the plaintiff from Australia becoming practicable in the reasonably foreseeable future … the plaintiff’s detention was unlawful …[and] the plaintiff’s continued detention is unlawful,” Gageler ruled.

This overturned a 2004 decision made by the High Court,which upheld the constitutional validity of indefinite immigration detention in the case ofAl-Kateb v Godwin.

Why was the High Court decision made?

Barrister for the plaintiff Craig Lenehan,SC,told the court his client was a Rohingya man,a member of a persecuted group in Myanmar,meaning he could not gain citizenship from that country.

The detained man had been imprisoned since he was paroled in 2018 and several attempts were made by the Department of Home Affairs to deport him,but were unsuccessful as he was not recognised as a citizen in any country.

In Lenehan’s written submission,he argued “aliens” in Australia have a freedom from being detained by mere administrative decision or action.

“The Commonwealth Executive cannot take away that freedom,” he wrote.

Gageler ultimately agreed with this argument,making the order that the government cannot detain people indefinitely if there was no prospect of deporting them in the foreseeable future.

Who are the 83 people released?

Murderers,sex offenders and people smugglers are included in the detainees released from immigration detention on bridging visas.

Immigration Minister Andrew Giles confirmed on Tuesday three of the detainees were murderers and “several” were sex offenders.

Western Australia’s premier Roger Cook told parliamentary question time on Tuesday that seven of the state’s 32 released were known sex offenders.

The released detainees include brothers,Juma and Zackaria Chol,whogained refugee visas after fleeing Sudan in 2001. The pair had their visas cancelled by the former Coalition government after they were convicted and jailed for attacking a man with a baseball bat in March 2012,fracturing the victim’s skull.

Gus Kuster,who was born in Papua New Guinea and claims Torres Strait Islander heritage,has also been released after being placed in immigration detention after several stints in jail for domestic violence and drug,motor vehicle and weapons-related offending.

Former Sudanese child soldier William Yekrop is another freed detainee after 10 years in immigration detention. He was convicted of offences relating to property damage,drink driving,dangerous driving,violence and miscellaneous other offences.

Former Malaysian prime ministerial bodyguard Sirul Azhar Umar is also walking free after being held for almost nine years.

Sirul wassentenced to death over a gruesome,politically charged murder in 2006 of pregnant 28-year-old Mongolian translator and model Altantuyaa Shaariibuu. The Australian government does not deport people who are facing the death penalty,making Sirul’s detention indefinite.

Why is the decision controversial?

Immigration Minister Andrew Giles and Home Affairs Minister Clare O’Neil have acknowledged the risk the individuals convicted of significant crimes pose to the community and areconsidering new laws and regulations available to it to deal with the fallout.

“Those crimes and those people are absolutely despicable. I’m raising three children in this country and I can tell you that if there was anything in my power to keep these people in detention I would absolutely do it,” O’Neil told Seven’sSunrise program on Wednesday.

In the government’s released response on Tuesday,it stated the individuals were under strict conditions,including regular reporting of their whereabouts,personal details and social media profiles to authorities.

“The government is exploring further measures,including legislative and regulatory options,to ensure community safety as we work through the implications of the High Court’s decision noting the court is yet to hand down its reasons,” the statement said.

Dutton disagreed,saying on Wednesday the government should have been prepared for this outcome and that it had the ability to make legislative changes without the High Court’s reasons.

“This is not the first time that the High Court has handed down a decision and there will have been arguments,there will have been understandings by the government solicitors in relation to the matters and the facts of the case,” he said.

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