In order to achieve fair democratic representation, the Australian Constitution states “the number of members chosen in the several States should be in proportion to the respective numbers of their people”. Each state’s population changes constantly, and therefore the Australian Electoral Commission (AEC) must regularly ensure that each state and territory has their fair share (entitlement) of members in the House of Representatives.
As there is one member for each Federal electorate in each state and territory, if the entitlement to the number of members does change, so too must the number of electorates. This requires a ‘redistribution’ of the electoral boundaries. This post explains how the AEC determines the number of members in the House of Representatives, how many are allocated to each state and territory and how often that allocation is reallocated.
Currently, there are 150 members of the House of Representatives. Why 150? Because the Constitution states “the number of such members shall be, as nearly as practicable, twice the number of senators [for the states].” If we have 72 state senators, then our starting figure for the number of members is 144. The ACT and NT each have two members, bringing the total to 148, and Tasmania provides the extra two members (see below) to make 150.
The most recent member entitlement determination was in November 2014. The population of Australia was 22,793,303. By dividing that by the 144 members required, we get a ‘quota’ of 158,287. In order to determine how many members are needed in each state and territory, we divide its population by the ‘quota’. Using New South Wales as an example, dividing its population of 7,500,617 by the quota gives 47 members. There is an exception which is Tasmania. Its population was 514,684 which would result in only 3 members but the Constitution says that there is to be a minimum of 5 members per state. The AEC has more detailed information on calculating representation entitlements of states and territories.
Entitlements are checked one year after a new parliament, and the November 2014 data shows the proportion of the Australian population residing in NSW decreased enough that it will be allocated one fewer members at the next federal election. Western Australia’s proportion increased and that state will be entitled to one more member. All other states and territories’ entitlements will stay the same.
Therefore, one electoral division has disappeared from NSW and one has been created in WA and so the borders of electoral divisions have been redrawn or redistributed in both of those states. The boundaries of each electorate are set by the AEC considering factors such as current population, three-year forecast population, geography, infrastructure, and a two-part community consultation process. Since the establishment of the AEC in 1984, Parliament has had no power to reject or amend electoral boundaries.
In NSW there will be one fewer division and two divisions will be renamed. The division of Hunter has been abolished, the division of Charlton has been renamed Hunter, and the division of Throsby is renamed Whitlam.
The map below shows the changes in the electoral boundaries in a selected area of Western Australia. The electorate of Burt has been created by moving the electoral boundaries of the surrounding electorates of Swan, Tangney, Hasluck, and Canning. In turn, electorates beyond have all had their boundaries changed too. When there are changes to electoral divisions, they come into effect at the following election.
A good example of population and geography/infrastructure influencing electoral boundaries is the recent redistribution in the ACT. The number of electoral divisions remains at two, but the division of Fenner (previously named Fraser) has had its southern boundary moved further north in order to evenly divide the forecast population of the ACT with the division of Canberra to the south. The reason for this is that population growth has been concentrated in the northern part of the ACT. The map shows that the previous electoral border was the waterway formed by the Murrumbidgee River, Lake Burley Griffin, and the Molonglo River. Now, where the border has changed, it uses major roadways instead.