The tax is part of a poverty plan that is one of the Greens' main priorities this campaign - a 1 per cent tax on people's net's wealth over $1 million and 2 per cent on wealth over $2 million.
But Labour leader Jacinda Ardern and finance spokesman Grant Robertson have repeatedly ruled it out.
"I consider that the last roll of the misinformation dice," Ardern said yesterday of National's continued insistence about the wealth tax.
"Any suggestion of picking up other parties' plans is mischievous and wrong, and I don't know how many times we've had to restate that."
This morning, asked about the wealth tax on Newstalk ZB, Ardern said: "We have ruled it out. And I've done it multiple times."
She said the major party forming a government should set the direction on tax policy, and her party's "primary" proposals were a new top tax rate and a digital services tax.
But Collins remained adamant a wealth tax would become realty under a Labour-Green government.
She said it in a party press release, in an email to supporters, over a bullhorn at a busy intersection, and again when talking to media yesterday.
"There should be a lot of people worried that if you you've paid off your house in Auckland and you are retired and you happen to have some money in the bank, then you're probably going to be subject to a wealth tax if James Shaw gets his way," Collins said.
"Do you want a wealth tax?" she asked over a loudspeaker to supporters – "no!" yelled a chorus of volunteers wearing blue windbreakers, all holding signs.
"What does a wealth tax mean?" she yelled. After a confusing couple of seconds with no reply, Collins finished the chant herself: "Labour/Greens!"
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