Hamilton looks likely to remove fluoride from its water in a vote from which at least five city councillors say they will abstain.
A Hamilton City Council tribunal examining the topic has re-ignited intense public debate on the issue, with 89 per cent of the 1,557 submissions made to it in favour of stopping fluoridation. In 2006, 70 per cent of residents who voted in a referendum backed fluoride.
Critics believe next Wednesday's vote could be a foregone conclusion after five of the 12 councillors stepped aside, citing conflicts of interest.
One source, who couldn't be named because of their role at council, suggested councillors were ducking for cover on a contentious subject before this year's local body elections.
Three councillors - Ewan Wilson, Pippa Mahood and Martin Gallagher - were warned by the council's lawyers to withdraw from the tribunal hearings because they were elected to the Waikato District Health Board, which supports fluoridation.
That takes out three who, at least in theory, support fluoride.
Wilson said the three had no choice but to obey the council's legal instruction.
Tompkins Wake partner Lachlan Muldowney said in a letter to council chief executive Barry Harris that councillors adhering to the health board stance had a fixed position to support continued fluoridation.
"In this regard, they cannot demonstrate bringing an open mind to the decision-making," Muldowney wrote.
"An inherent conflict of interest exists which can only be resolved by them stepping down from decision-making."
But Mahood and Gallagher abstained from a DHB vote to endorse its fluoride policy.
Wilson, who has previously voted in favour of fluoride, said the case was less clearcut for two other councillors, John Gower and Maria Westphal, who opted out of the tribunal at the last minute.
Gower reportedly said he believed he had compromised himself by publicly revealing a bias against fluoride.
Councillor Angela O'Leary made similar comments but did not remove herself from the tribunal.
Westphal stepped aside because she seconded a motion last year by councillor Dave Macpherson to remove fluoridation from Hamilton water by July 1.
But Macpherson has not withdrawn and apparently intends to vote this week.