Police Minister Judith Collins says nothing can excuse police mishandling of child abuse cases in the Wairarapa.
The Independent Police Conduct Authority has released the first of two reports on Tuesday into the way police have dealt with child abuse files.
Ms Collins says the report shows cases reported to police in the Wairarapa between 1999 and 2006 were not dealt with in a way the public would expect.
She says it is a sad story, and she is distressed for the victims involved.
Ms Collins says police have undertaken a nationwide audit and made significant changes.
An authority investigation revealed police files were inconsistently entered into the national computer system and were unreliable.
The authority began a national inquiry into child abuse investigations after a backlog of more than 100 case files was discovered in the Wairarapa district.
In its audit of case data, the authority said it had difficulty in getting the information it requested from the 12 policing districts.
It says some computer case files did not match the physical files and could not be relied upon to show a case's progress.
Police Commissioner Howard Broad says this was disappointing, but most cases stood up to thorough inspection.
Mr Broad says he is confident no children have suffered because files were ignored or mishandled.
But anti-family violence group Shine says there is every possibility children would have suffered because police officers left their cases unchecked.
Shine executive director Jane Drumm says the situation is unacceptable.
The report recommends most of the burden of file recording should be shifted from investigators to filing staff.
The Wairarapa district fared the worst in the investigation. Justice Lowell Goddard says it still had the highest backlog at more than 100 cases.
