The political leaders campaigning for the March 20 Tasmanian election — Premier David Bartlett, Opposition leader Will Hodgman and Greens leader Nick McKim — have yet to commit to the most obvious reform needed in the state.

In a parliamentary system in which the Upper House is largely independent and the Lower House is sparse in terms of its number of MPs, it means there are insufficient members in any elected government to form a legitimate ministry.

There are 25 MPs in the Tasmanian House of Assembly, elected by proportional representation, five in each of the five electorates: Bass, Braddon, Denison, Franklin and Lyons. Under the Hare-Clark voting system, which is similar to the Senate’s, the most MPs a government can expect is 15. The present Bartlett government has 14. Of those 14, one is speaker and seven are ministers.

On March 20, it appears unlikely that either Labor or the Liberals will win the 13 seats necessary to govern in their own right, but one of them will surely govern, with the Tasmanian Greens holding the balance of power.

Neither party will give the Greens a seat in Cabinet and the Greens don’t expect one. Therefore, of the 10, 11 or 12 people elected to form the new government of Tasmania, the great majority will walk straight into Cabinet, no matter their experience, leaving a backbench the size of the back seat of my Subaru.

This latest parliament has shown the poor performance by inexperienced and ill-equipped ministers who have to handle their own issues as well as those that involve negotiations with their counterparts in Canberra and the other states.

Tasmania cannot be governed by 25 Lower House MPs. It has to be 35 at least, as it was up until 1998 when, in their wisdom, Liberal premier Tony Rundle and Labor leader Jim Bacon conspired to reduce the numbers to try to rid Tasmania of the Greens.

The Hare-Clark system was not designed to give independents or minority parties the balance of power but that is how it has evolved, with the rise and staying power of environment-based political parties in Tasmania, who have found an electoral system tailor-made for their purposes.

In 1989 it delivered the Greens the balance of power for the first time and, inter alia, triggered Edmund Rouse’s attempt to buy off Labor MP Jim Cox to defect to the Robin Gray Liberals to restore Gray’s defeated government. Cox, who retires at this election, blew the whistle.

The Rundle-Bacon rationale nine years later was to get rid of the Greens by increasing the size of the vote, the quota, that a candidate needed to get elected. With seven members in each electorate, the quota was 12.5% of the vote plus one. With five members in each electorate, the quota rose to 16.66% of the vote plus one. The trouble is that the Greens can now achieve 16.66% and more in most electorates, or get so close to it that they win the final seat.

It seems that no matter what the two major parties decide about the future size of the House, the Greens will for ever be a thorn in their side. If they go to 35 seats, the Greens may well win two seats in each of the southern electorates of Denison and Franklin, where environmentalism and a sense of the perverse and of mischief prevail.

So if, in a 35-seat House, the Greens can expect to win seven seats it means that one of the major parties has to win 18-10 to secure majority government. That looks highly unlikely.

The conclusion: a stalemate, unless the Greens are included in the gene pool of any Cabinet.

If Labor and the Liberals want to get rid of the Greens, form government in their own right and have a healthy backbench, they are going to have to change the electoral system to single-member constituencies. They would kill off Hare-Clark.

But what do they say?