The sort of manipulation of electorate boundaries that goes on in American state legislatures is known as ‘gerrymandering’. The aim is usually to draw boundaries that maximise the number of parliamentary seats won by a party on its available vote. Deliberate gerrymanders for this purpose have been much rarer in Australian politics than in the United States.

Hot Tip: Gerrymander

The word ‘gerrymander’ originated in 1811 in Massachusetts, USA, when Governor Elbridge Gerry drew a wiggling electoral boundary designed to favour his party. Discussing the strange shape of the electorate, someone suggested it looked like a salamander. A newspaper editor replied ‘I call it a Gerrymander!’ and introduced the expression in his newspaper. Gerry’s electoral manipulation duly worked to his party’s advantage and ‘gerrymander’ gradually gained wider usage.

How do gerrymanders work? Consider the following simple example, involving 12 voters, six of whom support Party A and six Party B. In a fair electoral system containing four electorates, we would expect the boundaries to be drawn so that Party A would win two electorates and Party B to win two electorates, as in the following diagram.

Voting example diagram

We could draw the boundaries differently so that with the same number of votes, Party A now wins three electorates to Party B’s one.

Voting example diagram

Equally, we could redraw the boundaries to give Party B three wins to Party A’s one.

Voting example diagram

While gerrymanders are generally used to benefit parties, they have also been used in the United States to improve the chances of members of minority ethnic groups such as African or Latino Americans being elected. Before the courts began to restrict them, these efforts led to the drawing of strange looking electoral boundaries that joined up geographically separate ethnic communities.

Australian electoral boundaries have not been designed with this purpose in mind. Under the Commonwealth Electoral Act, redistribution committees must ‘give due consideration’ to an electorate’s ‘community of interests … including economic, social and regional interests’. This ‘community interest’ consideration has not been applied to improving minority ethnic representation. The other considerations stipulated by the Act are the proposed electorate’s ‘means of communication and travel’, ‘physical features and area’ and existing electorate boundaries. These considerations tend to produce compact electorates in Australia, which follow natural or artificial boundaries such as rivers and major roads.

Although deliberate gerrymanders are not a feature of Australian elections, parties sometimes win more than 50 per cent of lower house seats with less than 50 per cent of the lower house votes. At the 1998 federal election, for example, the Labor Party won almost 51 per cent of the House of Representatives vote to the Coalition parties’ 49 per cent. The Coalition nevertheless won more seats than Labor and therefore formed government. At the 1990 federal election, the pattern was reversed. The Coalition won just over 50 per cent of the vote but Labor won more seats and therefore government.

Similar outcomes have occurred at state and territory level. South Australia is the only jurisdiction whose laws require that electoral boundaries must be drawn up to ensure that a party winning 50 per cent or more of the lower house vote at a general election wins a majority of seats and is therefore able to form government.