In more than 15 years as mayor, Parker said, Yule had to be partly responsible for the poor relations with the regional council and the failure of the district council to deliver water that was safe to drink.
"He should be resigning as mayor, and there is no way that these appalling failures should be rewarded by his being elected to central government."
Yule said the relationships between the authorities that the judge referred to were those of staff and not of elected members, and that the panel said there were failings among the different organisations, but no fault or blame was laid for these leading to the contamination.
"I have stood by my community in this crisis and I am standing by my role as elected mayor to make this right.
"I respect the findings of the inquiry. I am not going to resign as mayor. As I have said I will stay in the role I was elected to until June 23 after the council has approved the spending that's been allocated for further water treatment."