House of Assembly seat boundaries still being adjusted to get elections decided on 50% vote
Focus on electoral fairness has turned to the 47-member House of Assembly in the 21st Century with the aim of having the party receiving more than 50% of the state vote forming government.
This hasn’t happened in three state elections won by Labor:
2014: Labor primary vote 35.8%, Liberal 44.8%.
Labor 2-party preferred 47%, Liberal 53
Labor 23 seats Liberal 22 seats
2010: Labor primary vote 27.5% Liberal 41.7%
Labor 2-party preferred 48.4% Liberal 51.6%
Labor 26 seats Liberal 18 seats
2001 Labor primary vote 36.4% Liberal 40%
Labor 2-party preferred 49.1% Liberal 50.9%
Labor 23 seats Liberal 20 seats
Even without 50% of the vote, a party can gain a majority to form government with the support of independents, as happened with the Labor party in 2014.
The Electoral Districts Boundaries Commission, set up in 1975. but follows inquiries and royal commissions going back to the 19th Century that sought ways to fairly divide the House of Asssmbly seats.
The present commission seeks to give each seat an equal population within a 10% tolerance. But the other issue is whether the electors in each seat have a common interest.
The Electoral District Boundaries Commission has adjusted the boundaries several times in trying to achieve this balance.
The boundary changes made for the 1918 state election were challenged by the Labor party on the grounds that, in varying the population for some regional sets (bit still within the 10% limit) they went away from the “one-vote-one-value principle.
The challenge went to the supreme court.
The House of Assembly has had 47 members since 1970, each coming from a single-member seat or constituency: 34 in the Adelaide area and 13 in rural areas.
House of Assembly members are elected by secret ballot using the preferential voting. To be elected, a candidate must receive an absolute majority: more than 50% of formal votes. If no candidate receives an absolute majority of first preference votes, the second preferences of the candidate with fewest first preferences are distributed to other candidates. Distributing next available preferences from the candidate with the fewest votes is repeated until a candidate is elected with an absolute majority.
