It will never be possible to determine the precise number of people abused because of large gaps and deficiencies in data collected at the time, the Royal Commission into Abuse in Care says.
Minister of State Services Chris Hipkins, who released the interim report Tāwharautia: Pūrongo o te Wā today, said it was a difficult read, and showed the enormity of abuse and trauma that had occurred.
The report is based on accounts of people abused in state care, provided up to the conclusion of the state redress hearing in early November at private and public hearings. It has no specific recommendations but what the Royal Commission has learned will ultimately inform its recommendations to government in a final report.
The royal commission has been tasked with examining historical abuse in the care of state-based and faith-based institutions. Redress hearings for those abused while in faith-based care were held in late November and early December.
The report said the estimate that about a quarter of a million young people were abused may be conservative.
The report said most of those abused came from the most disadvantaged or marginalised segments of the community, particularly from whānau Māori and Pacific families, disabled people and women and girls.
It said the two most common routes into state care were through criminal courts and the social welfare system.
The commission said the abusive behaviour ranged from - at the most common end - physical assaults and sexual abuse through to unreasonable physical restraint, cruel, inhuman and degrading treatment, as well as use of medication and medical procedures such as ECT therapy as punishment.
It said common factors in abuse cases included lack of vetting, training and oversight of those in positions of authority.
This also includes the absence of clear or safe procedures for making complaints of abuse and failures to respond to disclosures of abuse adequately.
Too much focus on financial implications
The interim report said the state's redress processes, including the Crown's approach to civil claims, had been overly focused on the financial implications to the state, rather than on providing satisfactory compensation to survivors and ensuring their wellbeing.
It said government agencies had full control of the claims processes and survivors who made claims were frequently disbelieved and forced to retell their experiences again and again, retraumatising them.
Hipkins said it was a deeply moving record of the state's past failings in looking after citizens in its care.
"I welcome this interim report, and I acknowledge the courage and determination of survivors who relived their painful experiences with the Royal Commission," he said.
"The hurt and anguish that has been caused in New Zealand's history is inexcusable.
"All children in the care of the state should be safe from harm, but as the testimony sets out all too often the opposite was true. We need to acknowledge these past wrongs and learn from them."
He said the Royal Commission's work would inform further improvements to today's care-and-redress systems.
"The government will also continue work already under way on other problem areas raised by survivors, such as possible options for a centralised claims process and considering reforms to how the Limitation Act is used.
"Survivors have told us they find it difficult to navigate the different redress processes operated by state agencies, and we are exploring whether a single entry point is possible for historic claims.
"The redress principles outlined by the Royal Commission in this report will help us progress these actions and the government will continue to listen and learn from the experience of survivors," Hipkins said.
'Much more' to be uncovered - inquiry chair
Inquiry chair Coral Shaw said that Tāwharautia: Pūrongo o te Wā was an important part of its work to date but was by no means the end of what it would find out.
"We will continue to uncover much more about the nature and extent of abuse in care over the course of this inquiry which will inform our final recommendations to the Governor-General.
"We are indebted to the survivors of abuse in care who have come forward to share their experiences - some of whom have now passed on. Without them, there would not be an Interim Report," Shaw said.
The Catholic Church's Te Rōpū Tautoko agency chair Catherine Fyfe said the church would study and learn from report.
"These reports will contain much important information and guidance that follow on from what survivors have told the Commissioners about their experiences," Fyfe said.
"Church leaders will be discussing these reports widely with the aim of looking at how we can continue to improve the way we help people who have been abused and the systems we have in place to prevent further abuse."
Archbishop of Wellington Cardinal John Dew said bishops and congregational leaders as well as many individual church members listened carefully to the survivors' experiences as they spoke at the recent Royal Commission redress hearings.
"We want the events of the past to be examined transparently and openly. We are deeply sorry for the harm caused to so many by the abuse they suffered, and we continue to express our profound sorrow."
Te Rōpū Tautoko is the agency that coordinates and manages cooperation between the Catholic Church and the Royal Commission. It was formed by the New Zealand Catholic Bishops Conference (representing the bishops of the country's six dioceses) and the Congregational Leaders Conference (representing Catholic religious congregations in New Zealand).