The Chief Ombudsman will launch an investigation into the way the Official Information Act is being used after the election and will include a probe into ministerial offices as part of the inquiry.
The probe comes in the wake of Nicky Hager's book Dirty Politics and questions over OIA information provided to Whaleoil blogger Cameron Slater.
Chief Ombudsman Dame Beverley Wakem said issues which would be examined included government departments having to seek "sign off" from their ministers before releasing information when there was no reason to do so.
She said there was "excessive reference upwards for approval" to release information when there was no good reason for doing so.
The Act was intended to increase Government and ministers' accountability to the public while allowing citizens to have a greater input into decision-making. It was passed in 1982, came into force two years later and has now been operating for 30 years.
Dame Beverley, who did not want to comment on Hager's book, said issues before the Office of the Ombudsman raised concerns about the capacity to handle requests and policies used by departments, rather than any alleged rorting of the system. "I haven't observed anything sinister.
"I have observed unnecessary steps and referrals upwards. I have heard of at least five layers of approval before something can be released. That's absurd."
She said the unnecessary upwards delays included referrals to ministers for approval to release information. There were also offices which had "delayed things beyond what is reasonable" while others did "incredibly well".
"There's actually fundamentally nothing wrong with the Act. What is wrong is the execution.
"It is people's understanding of the act and understanding of how to use it." She said many public service staff with expertise in the Act had been "rinsed" out of the system. She said there was an impact on staff with experience "if there's not very many of them left doing this" and they received a heavy load of requests each day.
Dame Beverley -- a former Radio NZ chief executive -- pointed to the public service sinking lid, saying "there's only so much blood out of a stone".
She said the office, which had previously told select committees it was cash-strapped, was "approaching having enough money".
In the past two years, she said extra resources had gone into training for public service staff with positive effect.
Dame Beverley, who is president of the International Ombudsman Institute, said she had been tempted to publish a league table of best-to-worst agencies, as other bodies did abroad.
"We haven't resorted to that in New Zealand but each day that goes by it becomes more tempting." She said the framework of the inquiry had been completed and it would be launched in the next few months.