Responsibility for the leak of budget information to Telecom has been placed squarely on the shoulders of someone described as a low-level civil servant.
Parliamentary messenger Michael Ryan has been named as the person who gave a confidential cabinet paper detailing plans to unbundle the telecommunications network to a Telecom employee.
Ryan was employed by the Department of Prime Minister and Cabinet, which is not part of the prime minister's own office, but a politically neutral public service department.
The State Services Commission report exonerates the Telecom employee and says the breach of security was solely that of the messenger
Ryan now faces dismissal and the matter has been referred to the police.
Chief executive of the Department of Prime Minister, Maarten Wevers, and the Cabinet Secretary submitted their resignations following the leaker being named.
But, Prime Minister Helen Clark said the leak was an act of gross and disgraceful dishonesty and says she will not accept the resignations in the wake of the security breach.
Clark says the systems used by the department have been the same for years and to her knowledge nothing like this has happened before.
Distinguished former public service head Graham Scott believes procedures in the department might need to be tightened. Scott, who once headed Treasury and served in the Prime Minister's department, is now an international public sector consultant. He said it is hard to stop all leaks but mechanisms do exist to make them unlikely.
But Clark says the best systems in the world can be breached if there is a deliberate intention to do so. She says she is pleased the matter has been referred to the police.
The State Services Commission report found that systems for handling sensitive documents such as Cabinet papers was generally sound, but should be reviewed in light of the leak.
State Services Commissioner Mark Prebble says the leak was a major lapse in performance for the department, and that will be taken into account in the annual performance assessment of chief executive Maarten Wevers.
For his part Wevers says he is ultimately responsible for his department and he expects to be called to account for what happened.
The National Party says despite the leak being found questions remain about the security around sensitive documents
National's State Services spokesperson Gerry Brownlee says it is hard to believe Michael Ryan knew how to find the particular document, given sensitive material is usually inside envelopes.
Brownlee says spin is being put on the story and his party will continue to push for a Select Committee inquiry.