The Ministry of Social Development has "apologised unreservedly" to the court after its shortcomings resulted in a child-abuse trial being aborted last week.
The 61-year-old defendant, who faces 42 counts of physical and sexual abuse of two girls in his care between 1994 and 2003, had been on trial for three days when Justice Paul Heath discharged the jury.
He told jurors in the High Court at Auckland that the situation had come about because of a failure by Child, Youth and Family to submit documents.
"It became apparent that the disclosure was incomplete to the extent that there was something in the order of 300 relevant documents that came to light," Justice Heath said.
The case came back before the court this morning, where lawyers discussed how to progress the matter.
Mathew Downs, representing the Ministry of Social Development, reiterated an apology which had previously been made to the court by government officials.
"The ministry acknowledges it failed to respond properly to information requests form the New Zealand police. No deliberate decision to withhold information was made," Justice Heath summarised.
Officials accepted they had made "significant errors", which were a result of systemic and human failures.
"The ministry apologises unreservedly to the court, the parties to the proceeding, the complainants and other witnesses for the errors, and sincerely regrets the need for the trial to be aborted because of them."
Mr Downs assured the court current practices were being reviewed to ensure similar issues did not recur.
Justice Heath set down a hearing regarding CYF disclosure for February 27 and the case will be back before the court again next month for allocation of a new trial date.
When the news of the trial issues broke, Louise Nicholas, an advocate for sexual abuse survivors, described the situation as "heinous" for the complainants.
"The courage it's taken for those women to come forward, go through the police investigation, then the start of the court process, is huge," said Mrs Nicholas, whose own complaint of sex abuse led to a commission of inquiry into police sexual conduct.