Questioning whether the Roast Busters' behaviour was abuse meant Child, Youth and Family did not properly consider how to care for the young people involved, a damning report has found.
Social Development Minister Anne Tolley, who was Police Minister when the Roast Buster complaints were laid, has today released a review into CYF's involvement in the case.
The Roast Busters are a group of mainly West Auckland youths who bragged on social media about having sex with drunk and underage girls.
In late 2011 police investigated complaints by teenage girls in relation to alleged offending by some of the Roast Busters. Charges were not laid.
CYF was also involved in responding to concerns about the group after receiving six referrals involving a total of 14 young people, a number of whom were named repeatedly.
Today's highly-critical report by the Chief Social Worker found:
• Miscommunication and misinformation between staff, with key agencies often not included in discussions.
• A lack of clarity of the role of CYF in responding to vulnerable young people, leading to a problem that young people fall into a "gap" between care and protection services and youth justice facilities.
• Decisions around interventions appearing to be process-driven and not based around what the needs were of the young people involved.
• Clear evidence that CYF at times approached referrals to another agency with the primary question being, "does our service need to do anything", rather than "what does this young person need".
Ms Tolley said CYF's operations were being improved, including clearer instruction on record-keeping, information-sharing and roles and responsibilities in relation to harmful sexual behaviour and vulnerable teenagers.
"What it showed ... was particularly the gap between care and protection and youth justice. And if a child isn't being prosecuted, who then looks after them and makes sure they are safe. So I think it showed a real gap in the process.
"Both the young men and the young women were vulnerable. Most of them were known to CYF, none of that was taken into account when CYF worked out how it then worked with those young people and supported them."
The way CYF and Police work together is also being changed, she said, and today's report would feed into the work of an expert advisory panel, which is currently preparing a business case on the overhaul of CYF.
Labour's spokeswoman for children Jacinda Ardern said she did not blame CYF staff, who were dealing with high workloads because of a lack of resources.
"The report says that CYF social workers spend 6 per cent of their time interacting with young people ... that is crazy, and obviously part of the problem."
There was also a major problem with how CYF made decisions about the case, Ms Ardern said.
"Because police made the decision that perhaps there wasn't legal grounds for them to intervene, CYF then took their cue from the police that perhaps there wasn't a role for them.
"That's actually why it was exactly a place for CYF to intervene -- their threshold test was simply around child harm, and that test was absolutely met. They could have done something, and they didn't."
Today's report is one of a number into the Roast Busters case. In March a report by the Independent Police Conduct Authority found several deficiencies in the original police investigations.