April 29, 2010 10:33am by David Farrar

Supplementary Member Scenarios

The Put MMP to the Vote lobby group has declared their preferred alternate scheme to be Supplementary Member:

The Put MMP to the Vote lobby today declared supplementary member (SM) its preferred voting alternative to MMP.

Co-leaders Peter Shirtcliffe and Graeme Hunt said an SM-elected Parliament would mean the number of list MPs would be slashed and “listers” would be stopped from subverting the will of the people.

“Under a 120-member Parliament, 90 members would be elected by first past the post with just 30 top-up MPs. If New Zealand opted for a 100-member Parliament –– something electors voted for in 1999 –– there would be just 20 list MPs,” Hunt said.

So a 90/30 system, or an 80/20 system if the size changed.

“What’s more, proportionality would apply to list seats only so it would be virtually impossible for list MPs to stop the party that won the most seats on election night from forming the government for the next three years.

“We have recommended SM because it provides for diversity but does not undermine electorate MPs. Under our system, electorate MPs would be denied a place on party lists. This would mean a defeated electorate MP could not return to Parliament via a party list. It would spell the end to electoral double-dipping.”

This is one of the things the public don’t like. However the solution has problems also – if electorate MPs are not on the list, they have less incentive to campaign for the party vote.

“We believe SM, with the appropriate safeguards, would restore faith to the parliamentary system, lead to greater voter participation in parties and foster higher turnouts in general elections.”

The Royal Commission on the Electoral System, which recommended MMP in 1986, said SM would be “likely to build on existing levels of [elector] participation” but added that popular control of Parliament under SM would not differ much from under first past the post.

“Single-party governments would continue to be the norm because the constituency results would not be altered by the allocation of the list seats,“ the commission said.

Now I always like to look at numbers, and how the last five MMP elections would have turned out if done under a 90/30 SM system.

To model this, one has to assume that a party would win the same proportion of 90 electorates as they did of the number that existed at each election.

Here’s 1996

In 1996 under MMP National needed NZ First to get a majority. Under a 90/30 SM, they would still have needed NZ First to govern. SM rewards parties that wins electorate seats, and NZ First won a lot that year.

In 1999, SM 90/30 would have given Labour an absolute majority, meaning they could have governed without the Alliance. Arguably this means the Alliance may have never disintegrated.

And in 2002, Labour would have gained a massive majority.

2005 is interesting. National and Labour would have ended up with 53 seats each, both eight short of a majority. Lab/Gre/Prog would be 56 and Nat/ACT 54. Don Brash could have become PM if United Future and Maori Party went with them. Helen Clark would have remained PM only if she could have got the Maori Party onside – Winston wouldn’t be enough.

As Helen had declared the Maori Party last cab off the rank, it is possible one may have ended up with a Don Brash led Government with the Maori Party, ACT and United Future.