Len Brown's office has spent almost a quarter of a million dollars on polls and surveys - but won't say why, citing privacy reasons.
The Herald on Sunday asked the Auckland mayor's office for details, including the reason for each, the questions asked, the number of people surveyed and the responses.
But Brown's office withheld the information, citing the "maintenance of the effective conduct of public affairs through the free and frank expression of opinions".
Canterbury University law professor and media law specialist Ursula Cheer was surprised by the reasons given, as involvement in polls and surveys is usually anonymous.