South Australia 2018 Archive

19

Map update – South Australia and Tasmanian upper house

I’ve recently completed two new maps for download and use: the (kind of) final boundaries for the 2018 South Australian state election, and draft boundaries for the Tasmanian upper house.

South Australia’s state redistribution was overshadowed by the federal election last year. A final set of boundaries was released late last year, with some significant changes to the draft boundaries in southern Adelaide, but these boundaries are stuck pending a lawsuit by the SA Labor Party. Both the first draft and final draft can be downloaded from the maps page, and the map is embedded here.

I’ve also completed the draft boundaries for the Tasmanian Legislative Council. The Tasmanian upper house consists of fifteen single-member electorates, but its members are elected in a very odd way: only 2-3 seats are elected each year, with members serving a six year term. Boundaries are redistributed roughly once a decade, with the sitting members assigned to finish their term representing a new seat.

There have been some major changes to the boundaries along the east coast of Tasmania. The three Launceston-area seats have remained largely the same, as have the four Hobart-area seats and the two rural seats to the west of Hobart. The west coast seat of Murchison has undergone minor changes.

The east coast seat of Apsley has been chopped up, while the seat of Rumney in the south-eastern corner of the state has been pulled in closer to Hobart, losing Sorell and the Tasman peninsula. A new seat of Prosser stretches halfway up the east coast from the Tasman peninsula to Swansea, while the remainder of Apsley has been moved into a new seat of McIntyre.

The seat of Western Tiers has been chopped up, with the north-western seats of Montgomery and Mersey expanding south and the south-western seat of Derwent expanding north. The remainder of Western Tiers has joined the remainder of Apsley as McIntyre, a strangely-shaped seat curving around Launceston, stretching from Cradle Mountain to Flinders Island.

I would expect the final boundaries for the Tasmanian upper house to be determined later this year, and the new boundaries will be used for the first time in 2018.

5

SA state redistribution – draft boundary analysis

screen-shot-2016-10-19-at-8-22-18-pmWhile we were all recovering from the federal election, South Australia was undergoing a redrawing of its state electoral map for the 2018 state election. The draft electoral map was released in mid-August, and I blogged about the underlying statistics driving the redistribution at the time.

It’s taken me some time to get back to this redistribution, what with the many territory elections, council elections and by-elections taking place following the federal election, but it’s now complete.

You can download the 2018 draft map here.

The last election produced a result of 23 Labor seats, 22 Liberal seats and two independents. One of those independents, Geoff Brock, sided with Labor to give them a governing majority, while the other independent, Bob Such, went on sick leave soon after the election and later died of cancer. During Such’s absence, former Liberal leader Martin Hamilton-Smith resigned from the party to join Labor’s cabinet. Labor subsequently won the Fisher by-election, giving them a majority in the House of Assembly.

The Electoral Districts Boundaries Commission is required by law to consider the party-political impact of the redistribution, with the aim of producing a result which will give a majority of seats to the party that wins a majority of the two-party-preferred vote. Despite this requirement, Labor won a majority in 2010 despite a Liberal vote majority after preferences, and achieved government again despite losing the vote in 2014.

In line with their mandate, the EDBC has redrawn the boundaries to boost the Liberal position. Assuming no change from the 2014 election vote which gave the Liberal Party 53% after preferences, the new electorates would give the Liberal Party 24 seats and Labor 22. The last seat, Frome, is drawn as notionally Liberal but is held by an independent. Theoretically this should mean that the Liberal Party should be able to win a majority with no change in their vote (assuming they can win back Hamilton-Smith’s seat), although this theory did not work at the last two elections.

45 electorates remain notionally held by the party that won them in 2014 (either at the general election or, in the case of Labor and the seat of Fisher, at the by-election). The other two seats are Elder, in southern Adelaide, and Mawson, which has moved from being a southern Adelaide seat into a regional electorate by stretching out to take in Kangaroo Island and the Fleurieu Peninsula. Both seats are held by Labor MPs but are now notional Liberal seats.

The following map shows the new electoral map. Click on each seat to see the post-redistribution margin, and who held the seat before the redistribution.

This map is only a draft – we should be expecting a final version of the map to be released in November.