Judith Collins has ripped into Gareth Morgan following the release of his drug reform policy last week.
The Government Minister and MP for Papakura took the philanthropist and wannabe politician to task on Ryan Bridge's RadioLIVE show on Sunday.
Ms Collins was asked for her thoughts on Dr Morgan's plan to legalise marijuana for people over the age of 20.
"If I had to deal with Gareth Morgan, I'd probably take up drugs," she said.
"Lots of money doesn't necessarily make you electable... so much money, so little sense."
Gareth Morgan's Opportunities Party is hoping to secure enough support to become a 'kingmaker' party, giving it a pivotal role in forming a new Government.
But it needs either an electorate seat or five percent of the party vote to get there.
Ms Collins is betting on that not happening, hence her scathing attack on the man who also wants a curfew on cats.
But former Labour Party President Mike Williams, who appeared next to Ms Collins on Bridges' show and has been involved in elections since 1977, warned her against such assumptions.
"The election that elected Donald Trump legalised marijuana in California and Justin Trudeau was elected on a police of legalising marijuana in Canada," he said.
"Now if you look at the Opportunity Party's policy as I did this morning, it is actually serious and well thought out.
"I think he could actually get his 5 percent and be a kingmaker."
Dr Morgan's party beat all other minor parties in a Newshub-Reid Research poll released in March with 0.8 percent support.
When asked if she had a moral problem with people smoking pot, Ms Collins' stance softened, indicating she was more against the man than the message.
"I actually don't have moral problems with other people who don't inflict difficulties or pain on other people, but that's not the law," she said.
"One of the issues around the law is that it's there, it needs to be upheld and if we were to change the law, then it's an entirely different thing."