She said she was "appalled" by Curtis Gregorash's claim. "Having said that one of the reasons I am undertaking of selected agencies in respect of their OIA practices is that anecdotally a number of people have told me similar stories," she said.
She said a planned inquiry to be launched after the election could see the Ombudsman's office using its Commission of Inquiry powers to compel evidence to be given under oath were there signs information was being hidden.
"Ministerial offices will be figuring in our inquiry and that is all I will say."
She said the Ombudsman's relationship with the government service was based on trust. Without that, she said, "we're all in trouble".
"We may as well kiss democracy goodbye. The work of this office relies in great measure in the maintenance of a high level of trust and integrity between ourselves and government agencies," she said.
"If our examination and investigation finds that has been betrayed or warped in any way that is something I am going to be taking very seriously and I think the public of New Zealand should be taking very seriously because it attacks the whole integrity of the system of governance."
Dame Beverley said whistleblowers should make contact with the Office of the Ombudsman if they had evidence of such practices.