Children's advocates and legal experts say allegations of sexual misconduct at two Oranga Tamariki residences show the worth of having a truly independent watchdog.
They fear shifting oversight of residences away from the Office of the Children's Commissioner to a government monitor from next month could mean other abuses stay hidden for longer.
It was during an unannounced visit to a youth justice facility late last week by a team from the Office of the Children's Commissioner that sexual misconduct allegations against one Oranga Tamariki staff member came to light.
The police are investigating that and a separate situation at a care and protection home for rangatahi with behaviour problems.
Tracie Shipton from VOYCE Whakarongo Mai, an advocate for children in care, said she was "horrified and disappointed" at the allegations but sadly not surprised.
"We always knew that young people in residences were a vulnerable group, and we've always been concerned about the secrecy and the gatekeeping that goes on in residences."
In November, the Office of the Children's Commissioner found "little to no progress" had been made on urgent recommendations from the year before at the Christchurch youth justice residence Te Puna Wai ō Tuhinapo.
Problems included ongoing violent assaults against staff and mokopuna, and complaints by children not being investigated.
Some staff had difficulties with "boundaries", discussing "hot dates" with rangatahi and supplying contraband such as cellphones and vapes.
Meanwhile, others felt so unsafe they wanted helmets, arm guards and riot shields on site.
However from 1 July oversight of Oranga Tamariki becomes the responsibility of the Independent Children's Monitor - under the auspices of the Education Review Office.
The government insists it will mean "more eyes and ears on residences", but critics say that loss of independence is dangerous.
As a departmental agency, the Independent Children's Monitor is limited to enabling government policy (commenting on services and standards), not criticising it.
Associate professor of politics and international relations Stephen Winter from the University of Auckland said as the ongoing Royal Commission into Abuse in Care showed, government agencies repeatedly failed to take appropriate action when children were being mistreated - often because they were not sufficiently independent of each other.
"The Children's Commissioner was created so as to have those watertight distinctions between the auditor and those being audited. And any move to water that down has raised red flags with a lot of people."
Oranga Tamariki's independent review into these latest incidents was only valuable if it produced change, he said.
"Many of these reviews are political moves, to be seen to be doing something. I'm not saying anything against people doing these reviews. But I think it's become a bit of a knee-jerk response when something happens: 'Oh, we'll have a review'."
Professor of policy studies at Victoria University Jonathan Boston agreed no agency could be trusted to monitor itself.
"At least in one of the cases the issues came to light as a result of that unannounced monitoring, and I think this simply highlights the worth of having an independent officer responsible for the wellbeing of children and young people."
A review in 2015 called for youth justice residences to be scaled back and care and protection facilities shut down. Children's Commissioner Frances Eivers said the new revelations were yet more evidence that children were not safe in these places.
"Both of them are meant to be last resort. We need to keep our children in the community, we need to treat them as children and not just break their spirits, which is what it does."
The new Children and Young People's Commission will continue its own monitoring under the United Nations Optional Protocol on the Convention Against Torture for the Ministry of Justice.
But as it's no longer the statutory monitor of the Oranga Tamariki system, its future focus will be at the discretion of its board.