The Children's Commissioner has told the Abuse in Care Royal Commission that his office has failed to properly monitor the state care system.
Since 1989, the Office of the Children's Commissioner has had the role of independent monitor of the practices and policies of Child, Youth and Family, which became Oranga Tamariki.
Judge Andrew Becroft said that the state care system has failed children and by implication, so had his office.
He acknowledged the suffering, hurt and violence experienced by the many who have been victims of state care.
"And the abuse they have suffered and the strength and courage they have demonstrated already in sharing their experiences."
His office had never been funded to comprehensively monitor young people in care, Judge Becroft said.
"Successive governments - despite the request to do so - have not in my view sufficiently funded, in any way nearly sufficiently funded, a state monitoring agency such as myself to carry out the job."
A separate statutory body needed to be appointed for children in care, he said.
"There must be a truly independent monitor of the care and protection system, empowered when necessary to speak out publicly, as a watch-dog."
There must also be a truly independent complaints system, he said.
"The systems in place now ... have not been independent and are fundamentally flawed."
Andrew Becroft at the Royal Commission hearing
Judge Becroft told the Royal Commission into abuse in care that large-scale care and protection residences in New Zealand "should be replaced with much smaller family-based homes for two, three or four children or young people but as a temporary option and as last resort".
"I am not advocating we change a bad system to a less bad system. Wherever possible where a child needs to be removed a child needs to be with properly resourced, supported and assisted wider family or kin care."
He described the existing residences as an old-fashioned model.
The Royal Commission is looking at state and faith-based care between the 1950s and 90s.
Judge Becroft asked the five commissioners to exercise their discretion to consider issues and experiences of those in care after 1999 and to the present day.
"I say that because it's often asserted there is a bright line in the past where abuse has stopped. No one can tell me when that date is.
"While one hopes that the extent and depth of abuse has reduced, we know that it is still happening."
He said the commission had the power to use its discretion to look into care before the 1950s as well.
"Please, please, please exercise it in a large and liberal way," he said.
Judge Becroft said he commended Oranga Tamariki for producing quarterly reports on abused and neglected children in care which reveals a 7-10 percent current abuse rate.
"Frankly that is likely to be the rock-bottom number because we know the power imbalance for children in care inhibits making complaints. The actual percentage is likely to be greater."
Information from the Australian Royal Commission into Institutional Responses to Child Sexual Abuse showed that it takes about 23-years after abuse has occurred for victims to disclose it, on average.