Justice Minister Andrew Little has flagged that referenda on cannabis law reform, euthanasia and MMP reform could take place at the same time.
Speaking to TVNZ's Q&A programme last night, Little said a Cabinet paper on the cannabis referendum was with colleagues at the moment but the detail of the referendum's form, whether it's binding or not, had yet to be decided.
The Government is planning a referendum on cannabis for personal use before or at the 2020 election as part of its confidence and supply agreement with the Green Party.
"There's a Cabinet paper that's being reviewed by various Cabinet ministers at the moment and I would hope that we'll make decisions before the end of the year," Little told TVNZ.
"One of the issues is, is it binding, is it not binding. There's still the question about the timing of it and various other questions as well. But it's certainly my strong preference ... that by the end of this year we'll have those principal decisions determined so we all know."
Little said a referendum on the question of euthanasia could also be held at the same time, following discussions with ACT leader David Seymour, who has been driving the issue, and a willingness by New Zealand First to support Seymour's End of Life Choice Bill if it went to a referendum.
"It is possible that there would be a referendum on euthanasia as well," Little said.
He also flagged a possible referendum on changes to the MMP system of representation.
"It has been floating around that if we're going to do a bunch of referenda, why wouldn't we put this question about whether we want to make those final tweaks to MMP, reduce that 5 per cent threshold to 4 per cent, get rid of the one-seat coat-tailing provision."
But he said no decisions had been made on that yet.
In 2012 the Electoral Commission recommended reducing the party vote threshold for entry to Parliament from 5 per cent of the vote to 4, and also abolishing the coat-tailing provision which means parties who win an electorate seat can bring in other MPs, regardless of whether they meet the threshold.
National leader Simon Bridges warns the Government not to reform electoral law just to protect its support parties.
Bridges says talk of reducing the party vote threshold for entry to Parliament from five percent to four, and abolishing the coat-tailing provision, is about entrenching the status quo - and protecting parties like NZ First.
"We looked at it, we thought keep it at five per cent, but if they want to keep it fair and democratic, I think the argument is for two or three per cent rather thanv four per cent, personally."
Bridges says they're important issues, and if that happens around the 2020 election it will be a distraction for voters.
He says the Prime Minister and her Cabinet need to think that through.