Hawke's Bay Regional councillor Tom Belford is refusing to answer an official request by Central Hawke's Bay mayor Peter Butler for his telephone and email records, saying it will set a harmful precedent.
However, this principle might not be enough to withhold information under the Local Government Official Information and Meetings Act.
On August 26 Mr Butler wrote to HBRC interim chief executive Liz Lambert, requesting all email and phone record communications of Mr Belford from August 8 to August 25.
"Of particular interest are any communications with Peter Fowler of Radio New Zealand, the Hawke's Bay Today, Simon Lusk, Russell Norman, and Genevieve Toop of Greenpeace NZ relating to either the Ruataniwha Dam or the Havelock North water contamination incident," he wrote.
In an email to regional councillors on Sunday, Mr Belford stated he was declining to respond to the request, "other than to confirm that I have had no contact whatsoever with two of the named individuals - Russell Norman and Simon Lusk."
Declining to provide information was a matter of principle, he said as he felt constituents had every right to expect they could raise issues with councillors in confidence.
"Sometimes the matters involved are rather sensitive, and these people clearly think they are communicating with me in confidence. I believe that's part of my role as a councillor is to hear what folks have to say," he said.
"If anybody out there in the public thought that any communication they had with me, or with any other councillor was automatically a matter of public record that would be totally chilling on the interaction between us and our constituents."
Mr Belford said all his official communications were done on a private mobile phone and email address, neither of which belonged to the council.
However, the Ombudsmen - official information watchdog - said the information requested would be covered by the LGOIMA if it was held in Mr Belford's official capacity as regional councillor.
Ombudsman Leo Donnelly said "The information would have to be made available unless there was a good reason under the LGOIMA to withhold it.
"As the requested information was about the Ruataniwha Dam, it seems likely that it may relate to Mr Belford's official capacity. If so, the information would be deemed to be held by the regional council."
Mr Donnelly said the fact that requested communications included emails sent through personal email did not affect the application of the LGOIMA.
"If the communication is made in an official capacity it does not matter how it was communicated."
Mr Butler received the response - without information - from council yesterday, and said "it makes me wonder a little bit what Mr Belford is hiding".
He would not comment on why he had requested the information.
When asked if he would complain to the Ombudsman, Mr Butler said "I can't see why not".