The government on Friday released a 200-page response to the final report of a commission of inquiry that examined child sexual abuse in government institutions.
The inquiry outlined grave failings over decades and described the state's response to abuse allegations since 2000 as too often inadequate.
In handing down 191 recommendations it found the Ashley Youth Detention Centre posed a current abuse risk.
It called for the centre to be closed "as soon as possible".
The government, which previously pledged to adopt all recommendations, detailed a three-phase implementation plan to be completed by mid-2029.
Attorney-General Guy Barnett says the response to the child abuse inquiry is a "milestone event". (Ethan James/AAP PHOTOS)
The government two years ago pledged to shut Ashley by the end of 2024, but more recently flagged a longer timeline as part of broader youth justice reform.
Friday's response said a master plan for the proposed new facility north of Hobart would be open for public consultation in the second half of 2024.
"This will inform the development application to council, which is expected to be lodged in 2025, with construction to commence soon after," the response said.
The inquiry lists the closure of the centre as a medium-term recommendation, to be completed by July 2026, something the government says it will achieve.
Attorney-General Guy Barnett described the response as a "milestone event".
"(There have been) 22 years of failure, systemic failure, across government institutions," he said.
Mr Barnett said the cost of implementing the recommendations was being figured out, noting $55 million had already been pledged since the start of the inquiry.
In line with recommendations, the response commits to a review of custodial stays at Ashley by July to determine whether they align with sentencing orders.
Former national children's commissioner Megan Mitchell will evaluate the centre's internal policies by July.
The government plans to implement more than 80 per cent of the inquiry's recommendations by the end of the second phase in July 2026.
It also plans to introduce legislation in early 2024 to set up independent monitoring of its progress.
The inquiry into child sex abuse made 191 recommendations and 75 findings. (Ethan James/AAP PHOTOS)
"The victim-survivors have done their bit, it's time now for the government - and all of us - to do ours," Labor opposition MP Sarah Lovell said.
"We will be closely scrutinising the implementation plan to ensure that this is the case, including at parliamentary hearings next week."
The inquiry held eight weeks of public hearings last year but said it was hampered from making some misconduct findings because of complex legislation.
It examined youth justice, education, out-of-home care and health with a particular focus on Ashley and the Launceston General Hospital.
It was told of abuse and neglect at Ashley and a lack of government action despite more than a dozen reviews and reports pointing to issues over decades.
It also detailed missed red flags by government and police in relation to a male nurse at the hospital who worked on a pediatric ward for nearly 20 years before taking his own life in 2019 when charged with child sex abuse offences.
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