A High Court's decision that forced the release of about 150 people from immigration detention is set to cost taxpayers $255 million over the next two financial years.
The federal government had to release the detainees after the High Court ruled keeping them in indefinite detention was illegal.
It led to the government rushing through legislation to monitor the newly freed detainees and establish a new preventative detention regime in a bid to return some to custody.
Budget documents released on Wednesday reveal the Australian Federal Police and Department of Home Affairs will bear the brunt of the "community safety measures" spending.
Home Affairs has budgeted almost $147 million over the next two financial years, while the federal police have allocated just over $86 million.
The Office of the Director of Public Prosecutions will spend nearly $17 million dealing with the fallout, while Services Australia will spend $3.2 million, the Attorney-General's Department $1 million and the Health Department $800,000.
Money for the 2025/26 and 2026/27 financial years was labelled "not for publication" in the budget update papers.
The opposition continues to slam the government's handling of the ordeal, accusing them of being flat-footed and not having legislation ready to go as soon as the court handed down its decision.
They have seized on the re-arrest of some half a dozen detainees for new alleged offences, claiming community safety was at risk from the release of convicted murderers and sex offenders.
The released cohort included such people who had served their time behind bars, as well as others who had committed relatively minor offences.
The government has not released a breakdown of the specific offences they were detained for committing, but Immigration Minister Andrew Giles has previously told Parliament there were three murderers and several sex offenders.
Court applications to have some of the cohort re-detained under the new preventative detention regime are being worked up by Mr Giles.
The Greens have expressed anger and accused the opposition of whipping up fear and hysteria over the small cohort, given prisoners who had served their sentences were routinely released around Australia daily.
