Explainer: What is preferential voting?

Preferential voting is a system largely unique to Australia, so what does it mean and how does it work? Calliste Weitenberg reports.

WHAT IS PREFERENTIAL VOTING?

Preferential voting is required in Australia. It's largely unique to our political scene, reflecting the number and diversity of smaller parties that participate in elections.

It is a system of voting that allows a citizen to individually number and rank all candidates for both houses of parliament according to their preferences.

It is employed when no one candidate or party wins outright, based on first preference votes.

It means a citizen's vote can still be counted, even if their first choice of candidate is eliminated due to a lack of votes.

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HOW IT WORKS

On a ballot paper, placing a number one against a candidate is considered the first preference or primary vote.

If no candidate secures an absolute majority of primary votes, the candidate with the fewest votes is then eliminated from the count.

The votes for this eliminated candidate are then redistributed among the remaining candidates according to the number two preference indicated on the original ballot.

This process of elimination based on preferences continues until a candidate secures an absolute majority.

Such a process enables a two-party system to ultimately emerge, whereby all votes are effectively divided between two major parties – in this case, the Labor and Liberal parties.

TWO SYSTEMS

There are two systems of preferential voting to elect the two sides of Parliament - one for the House of Representatives and one for the Senate.

To elect a candidate for a seat in the House of Representatives, there is simply a list of candidates, their party name and a box the voter must number.

To elect a candidate for a seat in the Senate, it is more complex. The voter has two choices. They can simply rank parties, listed above the line on the ballot paper or, alternatively, they can number all the individual candidates, which are listed below the line.

If you vote above the line, preferences are still employed. Your vote endorses the declared preferences of the party, recorded with the Australian Electoral Committee. This allows the party itself to control the flow of votes.

Voting below the line is complex and requires numbering every candidate, even those a voter may completely disagree with. In this year's election, the ballot paper with all candidates listed could reach a metre in length, by nature, a more time-consuming process.

HAVE A GO

Some online websites can assist Australians in working out their list of preferences ahead of the election. This list can then be printed and used at the polling booths in place of party How To Vote cards on the day.