Many MPs support four-year terms in Parliament - so why hasn't it happened?

New Zealand has one of the shortest Parliamentary terms in the world, languishing on a measly three years while other countries have as many as six.

Two referendums have been held over extending the term to four years - both have failed. But The Project asked MPs how many years they want to serve for - and the answer was a resounding "four" from both sides of the house. 

James Shaw from the Greens said four, Nick Smith from the National Party agreed as did Phil Twyford from Labour.

But why hasn't the public backed it?

Lara Greaves, a Politics and Policy lecturer from Auckland University says she errs on the side of caution when it comes to Government.

"I would have a leaning towards staying on a three-year term just because there aren't many stops on the power of Parliament," she told The Project on Friday.

"If we happened to elect a government which was either not performing very well or they were tyrants, we'd be able to boot them out after three years." 

But a longer-term could give Governments more time to fix long-standing issues such as welfare reform, water resource management and climate change. 

Deputy Prime Minister Winston Peters told the hosts of The Project another referendum won't work.

"The people on one side think 'well we won't win' so they don't vote for another four years and the other side is scared as well so they won't vote for another four years so you have a natural majority voting the negative."

However there is a way to push it past the line.

"As soon as the election ends, whoever loses should say 'okay we're for four years after the next election, right here, right now," he said.

"And in fact, if they were smart they'd say 'you're in for four years now' if that happens then you can go to the public and say 'we're here united for a four-year term, will you endorse it?"

He even said he would do it come the next election - but New Zealand will have to wait until September to see if our short terms could become that little bit longer.