Serial sex offender Robert John Fardon to be re-released from prison

Serial sex offender Robert John Fardon is to be released from prison after claims he was plotting an escape from supervised accommodation were found to be unreliable, a Brisbane court has heard.

Fellow sex offender Robert Riddler tipped off authorities that Fardon, 65, was planning to run away from his Wacol accomodation, where he had been living under a 24-hour curfew since his release from jail in December.

Riddler claimed Fardon had up to $2,000 in a bank account and wanted Riddler to source a vehicle for him and drive him to the Gold Coast region so he could escape over the NSW border.

During proceedings at Brisbane Supreme Court Jonathan Horton, the lawyer for Queensland's Attorney-General Jarrod Bleijie, said there was no available evidence to back the claims and admitted their source was unreliable.

Mr Horton said the crown would not be taking the matter further.

"Ethically, I'm not in a position to take the application further," he told the court.

Fardon has been behind bars since the allegation was made on September 2 and will now be returned to his supervised accomodation.

Fardon's lawyer Dan O'Gorman sought legal costs on behalf of his client and said Mr Bleijie should have exercised more caution before bringing the case to the courts.

Mr Riddler was "grandiose in his role as snitch" and Mr Bleijie knew the information was unreliable, Mr O'Gorman told the court.

Fardon has spent most of his adult life in prison after he was convicted of numerous sex offences against women and children.

Justice Lyons reserved his decision on costs until next week.

Mr Bleijie said Fardon would return to his strict supervision order, which included living in accommodation on correctional centre grounds, a 24-hour curfew and wearing a GPS tracker.

He said Corrective Service staff acted quickly and appropriately on reasonable suspicion.

"While the Supreme Court found Corrective Services acted on reasonable suspicion, today it ordered Fardon be released due to the informant refusing to give evidence," Mr Bleijie said.

"We share the community's frustration when dangerous offenders are released and we will always fight to ensure they are kept away from the community."

Premier Campbell Newman said the State Government's primary goal was to protect the public.

"We'll work as hard as we possibly can to ensure that [Fardon] is ideally incarcerated," he said.

"If we can't do that, we will make sure that he is under 24-hour monitoring with a GPS bracelet, which is the situation that now stands."