Labour leader Phil Goff may have tried it, Prime Minister John Key hasn't and doesn't plan to - and ACT leader Don Brash wants it decriminalised.
The marijuana debate was still smoking in Parliament on Tuesday - after Dr Brash's suggestion on Sunday that the Class C drug should no longer be illegal, because it's tying up police resources.
The comments have split his party - with Epsom candidate and former police minister John Banks saying there's no way he'd back such a policy.
The suggestion of decriminalisation's been scorned by both major parties - and Mr Goff says if the issue came up in Parliament, his MPs wouldn't be getting a conscience vote.
He says Dr Brash has got himself into "an impossible position".
"There is now a very clear split between himself and the candidate on whose coat tails he hopes to come into Parliament. I don't think the ACT Party's position is sustainable in anyway," Mr Goff says.
The prime minister is also not interested in liberalising drug laws.
"I don't actually accept the argument that the bulk of police resources are being deployed to someone who smokes a joint on Saturday night."
Mr Key says he's personally never been interested in smoking marijuana, even as a university student, and says there's "zero chance" of it happening now.
Mr Goff was less clear on his own position.
"I've made the comment that I've never been a smoker - tobacco or otherwise - but I was a student in the 70s. I'm not going beyond that comment."
NZN