Ross Hart slammed a "very disappointing" letterbox campaign run by the Liberal Party in George Town in which election material claimed Labor would cut two local projects - but Mr Hart says the council had an "in writing" guarantee they would proceed.
In early May, George Town residents received Liberal material stating Labor would cut $6.85 million in projects in the council area - $4.4 million from the George Town mountain bike trail, and $2.45 million for the Regent Square redevelopment.
The material then linked the cut to Labor's promise for $50 million for Mona and $25 million for a Tasmanian AFL team.
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Mr Hart said it was misleading and a "shocking abrogation" of Liberal candidate Bridget Archer's role as mayor of George Town.
"Unfortunately we have, in particular in this electorate, a political party that is prepared for example to letterbox people in George Town telling them, despite what they know, that Labor was prepared to cancel regional grants, commitments that were made in writing to the electorate," he said.
"We've had scare campaign on scare campaign again, and who amongst you can tell me what the Liberals' positive story for Northern Tasmania was?"
Mr Hart said George Town Council - and other councils in Bass - had received a pledge from Labor that the projects would go ahead, but the Liberal Party proceeded with the letterbox campaign.
The two booths in George Town swung heavily to the Liberals - 11.9 and 11.2 per cent - eating into the Labor vote.
The issue of grants funding appeared in the election campaign when Labor Lyons MHR Brian Mitchell told the Glamorgan Spring Bay mayor that the grants announced by the Nationals would not go ahead under Labor.
Yet Labor now claims these commitments were in writing and were not in doubt.
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Ms Archer said there was enough uncertainty to warrant the letterbox drop, and denied it was a scare campaign.
"Early on in the campaign there was certainly uncertainty around whether or not the Labor Party was going to honour the regional grant commitments that were made to communities across Tasmania, including some in George Town," she said.
"That uncertainty came from within the Labor Party [itself] and their messaging was not very consistent across that issue.
"So, from our point of view, we thought that was a genuine risk."
Mr Hart contacted Ms Archer on Sunday morning to formally concede.