A long-time Dunedin councillor and mayoral candidate has told another candidate he's not up to the job because he has cerebral palsy.

Councillor Lee Vandervis said he told Joshua Perry this in a private conversation following a "meet the candidates" event, and that his comments have since been used against him as part of a deliberate smear campaign.

He said he told Mr Perry he was brave for standing for council but that, if he was successful, he would not be able to carry out the job of a councillor.

"He can barely breathe or speak, he's wheelchair-bound. To be able to make any speech he has someone hold a microphone for him, someone hold the paper in front of him and point to the words he has to say.

"All of that degree of disability means he's simply unable to do the job of a councillor."

Mr Vandervis, whose son is severely autistic, questioned whether the points Mr Perry made on his website and his Facebook page were even his own.

It was irresponsible for Mr Perry's father and campaign manager to be encouraging him to stand for council, he said.

"Who would kid their own son into thinking they could be a pole vault champion if they were in a wheelchair? I mean it's just ridiculous, is it not?

"Are you gong to say that, in your PC world, that you simply can't accept any reality?"

Mr Vandervis, who took out an advert in the Otago Daily Times on Thursday explaining his side of the story, said he was still confident of being voted back onto the council.

He said the campaign that had been launched against him because of his comments to Mr Perry could cost him the mayoralty.

"My sympathy for Josh, going up to him at the end of a meeting as he sat there all alone in his wheelchair and having a very empathic discussion with him, and the way that that has been distorted and smeared, is quite frankly catastrophic."

Joshua Perry, 24, has completed a diploma of marketing at Otago Polytechnic and works 20 hours a week as a marketing co-ordinator for an anti-violence group.

He said he was standing so that disability issues such as bad street and public transport design were given more prominence around the council table.

"I would want to see by next election two disabled people standing in every part of New Zealand. I think it's important that we encourage people with all diverse backgrounds to stand."

Mr Perry said the material on his Facebook page and website was all his own.

Mr Vandervis' comments had only made him more determined.

"I think his intentions were to intimidate me. But, rest assured, I'm not going to be intimidated."

Mr Perry's father and campaign manager, Ian Perry, said his son suffered from a physical condition, not a cognitive one.

Mr Vandervis was taking a deficit approach to what he was capable of, he said.

"We have spent our lives fighting against those very attitudes and we've really tried to encourage Joshua to take the bull by the horns and pursue his own dreams. And sometimes he falls flat on his face, but it seems like more often than not, he doesn't."

Apart from Mr Vandervis, Mr Perry had received nothing but praise from the people of Dunedin in standing for council and standing up for people with disabilities, he said.