Six Victorian children under 14 are being held in youth detention, with Premier Daniel Andrews' office conceding he erred when addressing parliament on the matter.
Mr Andrews signalled in question time on Tuesday that his government could pursue raising the age of criminal responsibility during this term in office if a national approach cannot be agreed upon.
But he was quick to stress no children under 14 were in the custody of the state's youth justice network.
"My last report, late last week, was that we had less than 100 young people in the youth justice system ... 98 I think was the number last Thursday," Mr Andrews said at the time.
"That's still too high. None of them are 10 years old. None. I'm happy to try and get a further breakdown but I don't believe any of them are 11 or 12 or 13 years old."
However a spokesperson for the premier's office confirmed on Thursday that the he "semi-misspoke" and that six 13-year-olds were, in fact, in detention.
Australian states and territories agreed to develop a plan to raise the age of criminal responsibility to 12 at a meeting of attorneys-general last year.
A draft report released this month recommended raising the age from 10 to 14 without exception.
The Northern Territory and ACT governments have committed to raise the age to 12 and 14 respectively, while Tasmania plans to raise the minimum age of detention to 14 but keep criminal responsibility at 10.
Liberty Victoria said it was vital the minimum age of criminal responsibility was raised to 14 in Victoria.
"This is not a matter that should result in compromise. Children don't belong in prisons," it tweeted.
The admission comes after new data revealing 37 children died in 2021/22 within 12 months of their last involvement with child protection, including two Aboriginal kids.
The Commission for Children and Young People also completed 41 inquiries into child deaths from June 2018 to January 2022 and highlighted a number of themes, including eight instances in which a case was prematurely closed.
In one instance, a two-year-old girl died in an accident at her family property while unsupervised by her parents after six previous reports to child protection.
Opposition child protection spokesman Matt Bach said the most vulnerable and traumatised Victorians were being systematically failed, noting Labor recently appointed its fifth minister to the portfolio in 14 months.
"Child protection shouldn't be an afterthought in government. It shouldn't be something to be shifted around each and every time to the newest and most junior member of the cabinet," he said.
Senior minister Lily D'Ambrosio said the government had invested more to improve outcomes and expressed sympathy over the difficulty of children protection workers' jobs.
Community and Public Sector Union Victorian branch secretary Karen Batt said child protection programs were short-staffed by 25 per cent, with 600 funded vacancies across the state.
