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Proportional representation

Preferential voting systems discussed above are generally used to elect one representative. Where more than one representative is to be elected from each electorate, proportional representation systems tend to be used.

Proportional representation has been used for federal Senate elections since 1949. It is also used in upper house elections in New South Wales, South Australia and Western Australia, lower house elections in Tasmania, Legislative Assembly elections in the Australian Capital Territory and some local council elections.

The most common forms of voting and counting votes used in these elections are variations on the ‘Hare-Clark’ system. The system is named after the nineteenth century London barrister Thomas Hare and the Tasmanian Attorney-General Andrew Inglis Clark, who altered Hare’s system and campaigned successfully for its introduction in colonial Tasmania. The Hare-Clark system is a ‘quota-preferential’ system. This means that successful candidates must win a quota of all the valid votes cast and that preferences from other candidates can be included in a winning candidate’s quota.

Preferences in Senate Ballots

Hare-Clark systems are complicated both for the voters who have to use them and for the officials who have to count the ballots cast. In Senate ballots between 1949 and 1984, voters had to indicate preferences for all of the candidates on the Senate ballot paper. When there were only a few Senate candidates, this was relatively easy. By the late 1970s, however, dozens of candidates were contesting Senate elections. The requirement to fill in large numbers of preferences meant that almost one in 10 voters made mistakes on their Senate ballot papers, resulting in their votes not being counted.

The Hawke Government dealt with this problem in 1983 by introducing reforms to allow voters the option of indicating by a ‘1’ the party or group they wanted to vote for in Senate elections. This ‘group voting ticket’ method of voting is often called ‘above the line’ voting, because the registered parties’ names appear on the ballot paper above a thick line separating them from the names of the individual candidates, which appear ‘below the line’. Voters could now vote with a ‘1’ in a party box above the line, or else fill out preferences in all the boxes ‘below the line’. Voting above the line quickly became extremely popular in Senate elections, with around 95 percent of voters using this method and only five percent preferring the older ‘below the line’ method. Variations of these ‘above’ and ‘below’ the line options are used in state upper house elections in New South Wales, Victoria, South Australia and Western Australia.

The 2016 Changes to the Senate Ballot

What happened to the preferences of voters who voted about the line? In elections between 1984 and 2013, each political party registered the way that it wanted the preferences of voters who voted for it above the line to be distributed among all the candidates on the Senate ballot paper. This gave the parties control over which other parties would receive votes that could not be used to elect one of their own candidates (see below). At the 2013 election, a group of small parties used this feature of the Senate voting system to channel preferences to each other. This strategy resulted in some candidates with small numbers of initial votes to win seats in the Senate. Ricky Muir of the Australian Motoring Enthusiast Party, for example, won 0.5 percent of the first preference votes in Victoria but gained a Senate seat through accumulating preferences from other parties.

After much debate about this development, the Coalition Government, with the support of the Greens, passed amendments to the Commonwealth Electoral Act 1918 that removed the ability of parties to direct Senate preferences to other parties. A ‘1’ vote above the line for a party could now only be used to elect candidates from that party. The amendments stipulated that voters who voted above the line had to indicate preferences for at least six parties, by numbering at least six party or group boxes above the line. Voters who wanted to vote for individual candidates below the line could still do so by numbering at least 12 candidate boxes. Slightly confusingly, the amendments allowed Senate votes to be counted as valid if a voter numbered fewer than six boxes but numbered at least one box above the line, or numbered fewer than 12 boxes but at least six boxes below the line.

The specific effects of this move from full preferential voting to optional preferential voting in Senate elections are difficult to predict. It will make it impossible for candidates to be elected via the path that Ricky Muir and others took in 2013. In this way, it will reduce the chances of very small parties with little electoral support achieving Senate representation. Whether it will favour any of the more established parties over others is unclear. It is almost certain to result in some candidates being elected to the Senate without achieving a full quota (see below), particularly if voters continue their habitual practice of just voting ‘1’ above the line.

Quotas in Senate Ballots

Hare-Clark quotas are calculated by dividing the number of valid votes by one more than the number of places to be filled, and then adding one vote to the result. The size of the quota is thus determined by the number of places to be filled and the number of valid votes. In the 2013 half-Senate election, the quota that candidates in New South Wales had to reach to be elected was as follows:

4,526,382 valid votes + 1 = a quota of 646,627 votes
6 Senate places + 1

In the 2011 New South Wales Legislative Council elections, the quota to be reached by successful candidates was as follows:

3,948,985 valid votes + 1 = a quota of 179,501 votes
21 Legislative Council places + 1

Most of the difference in these New South Wales quotas is explained by the difference in the number of places to be filled in each election (six for the Senate, 21 for the Legislative Council). In percentage terms, the quota for a half-Senate election is approximately 14.3 percent of the overall vote, while for the New South Wales Legislative Council it is approximately 4.5 percent.

For double dissolution federal elections such as 2016, the quota in each state is smaller than for normal half-Senate elections, since twelve rather than six Senators are elected. For argument’s sake, if as many people in NSW cast a valid vote in the full Senate election in 2016 as did in 2013, the quota will be as follows:

4,526,382 valid votes + 1 = a quota of 348,184 votes
12 Senate places + 1

Counting the votes

Vote-counting for Hare-Clark systems is complicated. It has three main stages. The first stage is to determine which candidates have a quota or more of first preference votes. The first candidate in the Senate groups put forward by the Labor and Coalition parties always get more than a full quota in each state at Senate elections. In 2010, for example, the first candidate in the Coalition group, Concetta Fierravanti-Wells, won 1,610,385 first preference votes, or 2.71 quotas. Most of these votes were cast for Coalition above the line. John Faulkner, the first candidate in the Labor group for New South Wales, won 1,515,446 votes, or 2.55 quotas. Fierravanti-Wells and Faulkner were declared elected.

The second stage in the count is to distribute the surplus votes won by candidates like Fierravanti-Wells and Faulkner; that is, any votes over a quota that they do not need to get them elected. These surplus votes are transferred according to second preferences using a ‘transfer value’ to allocate them to other candidates. The transfer value is the total number of votes won by a candidate, minus the quota, divided by the original total. For Fierravanti-Wells, this transfer value was:

1,610,385 – 593,218 = 0.632

All the second preferences of voters who gave their first preference to Faulkner were then multiplied by 0.608 to determine how many votes should go to which other candidates. As a result, the second candidate on the Labor group, Matthew Thistlethwaite, was elected. The same process was carried out with Coalition votes, resulting in the election of the second Coalition candidate, Bill Heffernan.

Thistlethwaite and Heffernan both now had surplus votes. In cases like these, the surplus votes are again distributed using newly calculated transfer values. In 2010, this process added to the votes of the third Labor and Coalition candidates but did not give them enough votes for a quota. Two Senate places for New South Wales thus remained unfilled at this point in the count.

The third stage of the Senate count is to eliminate the most unpopular of the remaining candidates in turn and distribute their preferences to other candidates, as in House of Representatives counts. Many of the remaining candidates often only have a small number of votes, meaning that a large number have to be excluded before another candidate is elected. In 2010, after 259 counts, the third Coalition candidate Fiona Nash was elected on preferences. After 271 counts, the Greens Lee Rhiannon was elected to the final seat.

Proportional representation elections produce parliamentary houses that more accurately reflect the diversity of opinion in the electorate than houses based on first past the post or single member preferential or optional preferential systems. The greater proportionality of Hare-Clark systems can be seen by comparing votes and seats won for the House of Representatives and the Senate in 2013 (see the table below). The Greens won just one of the 150 House of Representatives seats with 8.9 percent of the vote, while the Coalition won 60 percent of the seats with 46 percent of the vote.

The Senate result better reflects the distribution of first preference votes. The over-representation of major parties is reduced and the Greens won as many Senate seats as their votes suggested they should. The same pattern occurs in state parliaments in which one house uses single member preferential voting and the other a version of proportional representation.


First preference votes and seats won in the 2013 federal election
  House of Representatives   Senate  
Party Votes % Seats % Votes % Seats %
Liberal-National Coalition 45.6 60.0 37.7 42.5
Labor 33.4 36.7 30.1 30.0
Greens 8.9 0.7 8.7 10.0
Others 12.1 2.7 23.5 17.5


Questions for Discussion

Why has single member preferential voting generally been chosen over proportional representation voting for lower house elections in Australia?

Which of the voting methods outlined above do you think is best? Why?