The Office of the Ombudman's review of the Official Information Act (OIA) was released this afternoon.
It concluded that most agencies were compliant with the OIA most of the time.
"The principle and purposes of the OIA remain sound, but there is more work to do," Dame Beverley said in a statement.
The review discovered that, on a number of occasions, ministerial officials had tried to limit the release of information or to change an agency's decision on an OIA release for "unwarranted reasons".
On all these occasions the agency rejected their proposals and the releases were compliant with the Act.
Ministers were also giving "mixed messages" to their departments about their expectations in complying with the OIA.
This had allowed doubt and suspicion to grow among the public about whether their requests would be fairly treated, the Ombudsman's review said.
"We found both government agencies and requests of information have developed assumptions about the motivations of each other, based on poor past experiences, which has had an impact on how the Act operates in practice and we want to see that changed," Dame Beverley said.
People who requested information often assumed that an agency's slow response or non-compliance was deliberate, when this was not always the case. It was sometimes the result of vague requests or poor engagement by agencies.
Nevertheless, a "cycle of distrust and suspicion" had been created between the public and agencies. This was compounded by the absence of high quality training on the OIA.
Nearly 80 per cent of agencies did not require their senior managers -- who were tasked with making the key decisions on OIA requests -- to undertake any level of OIA training.
Of the government staff who took part in the review, 60 per cent had not received any OIA training in more than four years.
And though some departments had begun publishing information proactively, such as on their website, nearly 80 per cent had no policy of proactively releasing documents.
In response to the problems identified in its report, the Ombudsman's office planned to begin compiling an annual report card on each department's compliance with the Act.
"The outcome of these reviews will be publicly reported to ensure the public has continuing trust and confidence in this cornerstone of New Zealand's democracy," Dame Beverley said.
It would also issue new guidance and resources for all agencies, and include a template for responding to requests and engaging with ministers' offices.
Dame Beverly said she expected greater leadership on the OIA, with clear public statements by ministers and CEOs about their expectations of compliance.
"The public needs to know their requests for access to official information will be treated appropriately and in accordance with the law by ministers and their agencies."