The Electoral Districts Boundaries Commission was established to review and carry out periodic redistributions of the boundaries of South Australia’s House of Assembly electoral districts

Redistributions prior to 1975

Legislative Council boundary decisions

The first electoral distribution of South Australia was in 1851 when the then province was divided into 16 single member Legislative Council districts for a partly nominated, partly elected one-chamber legislature.

Following the introduction of representative government in 1857, the Legislative Council became a single upper house district with 18 members. Between 1882 and 1973 the upper house was divided firstly into four and later five districts; membership varied with between 18 and 24 members. The boundaries were consequent on lower house redistribution decisions. In 1973, the whole of the State again became the electoral district for the upper house.

House of Assembly boundary decisions

The first distribution for a bi-cameral parliament in 1855-56 provided for 36 members elected from 17 House of Assembly districts. From 1857 to 1936 the majority of House of Assembly districts were represented by more than one member. Since 1936, effective 1938, each House of Assembly district has been represented by a single member. 1969 was the last year a redistribution took place before amendments to the Constitution Act in 1975 altered the legislative parameters governing boundary redistributions and created an independent Commission to determine all future redistributions.

The boundaries of electoral districts were originally determined by select committees of the legislature. In 1882, a Commission convened by the Parliament and chaired by the Attorney-General was charged with ascertaining the ‘best means’ of dividing the province into districts. In 1891, an unsuccessful attempt was made to set up a Royal Commission to specify districts with ‘equal populations’. Over the years redistribution proposals with more precise terms of reference were drafted and considered by Parliament, not all of which were accepted.

A number of ad hoc commissions were appointed under the 1917 Royal Commissions Act. Determinations were embodied in Acts of Parliament. The process was open to criticism as the objectivity of members assessing the boundary changes could be questioned, particularly prior to 1929 when members included serving members of the Parliament and the proposals could be accepted or refused by the Parliament.

Early divisions were based on population rather than enrolled elector numbers; the variation between the number of enrolled electors in each district was in some instances more than 50 per cent. Political, industry, country and metropolitan ‘interests’ exerted leverage on redistribution forums at various times although redistribution guidelines became increasingly specific. The first redistribution in 1929 conducted under the Royal Commissions Act was chaired by the Surveyor-General, included the Deputy Returning Officer for the State and excluded parliamentary members. It was bound by four terms of reference: community, communication, physical factors and existing boundaries. Population changes were specific terms of reference for the 1937 and 1969 redistributions.

Redistributions after 1975

The Electoral Districts Boundaries Commission (EDBC)

With the creation of the EDBC in 1975, the ability to accept or reject redistribution findings was removed from the Parliament. A specific set of criteria was established to govern future redistributions, and the principle of ‘one vote, one value’ was adopted.

1975 – 1985

The creation of an independent Commission removed the power to redistribute electoral boundaries from the hands of Parliament. The EDBC, in 1976 and 1983, had as a prime term of reference ‘one vote, one value’ - redistributing the 47 districts in line with the principle that the number of electors in each district must not vary from a quota by more than a 10 per cent tolerance. This effectively ended more than a hundred years of malapportionment. Periodic elections were held every two to three years and provisions were made for redistributions to take place after five or more years had elapsed between two general elections held on the same boundaries.

1985 – 2006

The change to a minimum three, maximum four-year term, population changes in a number of electorates and a failure to gain government in 1989 by coalition interests gaining the majority of the Statewide vote prompted a review of the EDBC's terms of reference. During 1990, the South Australian Parliament endorsed a Bill, supported by the electorate in a referendum on 9 February 1991, to amend the State's Constitution.

The measures allowed:

  • the date of the next redistribution to be brought forward to 1991
  • a review of the State's 47 House of Assembly district boundaries after every general election
  • the EDBC to consider wider criteria when reviewing and amending the boundaries, specifically the ‘fairness’ criterion - if candidates of a particular group attract more than 50 per cent of the statewide vote, sufficient candidates from amongst them would be elected to allow a government to be formed.
  • A significant redrawing of electoral boundaries took place in 1991 following the amendments to the Constitution and the introduction of the political fairness criterion. Only two districts remained unchanged though they were renamed. The 1994 redistribution abolished three districts, introduced three new districts, left six unchanged and adjusted others to conform with the redistribution requirements. Three districts were left unchanged in 1998, two districts had minor adjustments and eight districts were renamed after localities. In 2003, it was determined that 20 districts would remain unchanged from the 1998 redistribution, two districts, Bright and Mitchell, were subject to slight changes and the district of Elizabeth was renamed to Little Para.

2006 onwards

  • Fixed four-year terms for members of the House of Assembly with general elections occurring on the third Saturday in March every four years were introduced for the 2006 State election following the proclamation of the Constitution (Parliamentary Terms) Amendment Act 2001.
  • The 2007 redistribution adjusted the boundaries of 39 electoral districts with only eight remaining unchanged. No electoral districts were abolished, created or renamed. In 2012, the redistribution adjusted the boundaries of 38 electoral districts with nine remaining unchanged. The resultant changes affected approximately 88,000 electors. The boundaries of two districts, Bright and Frome, were redrawn so that they were moved from the Labor side of the pendulum to the Liberal side. While no electoral districts were abolished or created, the district of Norwood was renamed Dunstan, after the former South Australian Premier the Hon Donald Alan Dunstan AC QC.

Timeline of EDBC Orders

Reporting yearGazette dateOperation dateEffective date
1976 5 Aug 1976 25 Aug 1977 17 Sep 1977
1983 22 Sep 1983 22 Dec 1983 7 Dec 1985
1991 29 Nov 1991 29 Feb 1992 11 Dec 1993
1994 13 Dec 1994 13 Mar 1995 11 Oct 1997
1998 17 Nov 1998 17 Feb 1999 9 Feb 2002
2003* 20 Mar 2003 20 Jun 2003 18 Mar 2006
2007* 29 Mar 2007 29 Jun 2007 20 Mar 2010
2012* 21 Aug 2012 21 Nov 2012 Mar 2014

* Available on website. Previous EDBC Reports are available upon request.