So, how did the new Senate voting rules work in practice?

Australia has its new Senate. The Coalition will hold 30 seats, Labor 26, the Greens nine, and there will be 11 other crossbench senators.

In March, the government passed sweeping changes to the way Australians elect their senators. Group voting tickets, whereby voting “1” above the line meant your preferences were those already lodged by the party you voted “1” for, were abolished. This returned control of preferences to individual voters.

When debating the changes, which Labor and other minor and micro parties opposed, some senators made predictions about the make-up of the new upper house. Labor’s Jacinta Collins said:

The principal beneficiary of this new voting system will be the Liberal Party … The Liberal Party’s true motivation is to achieve lasting electoral dominance in the Senate for the conservative parties and, over time, a lasting Senate majority in its own right.

In fact, at the 2016 election the Coalition lost a net three Senate positions. It now has its lowest level of representation in the upper house in 70 years.

In February, Labor senator Stephen Conroy said:

The stated aim of these reforms is to wipe out all of the minor party players. On everybody’s calculations, they’ll all be replaced by either a Liberal coalition, a Green or a Labor senator.

In fact, the number of non-Green crossbench senators has increased from eight to 11.

Conroy also said:

… over three million Australians’ votes will be discarded. They’ll be exhausted; they’ll be not used to calculate who’s actually going to get into the Senate.

In other words, Conroy claimed more than 20% of Australians would vote and preference candidates who would be excluded before the Senate count was completed. In fact, the incidence of exhausted ballots was less than 6%, not including exhaustions from the last defeated candidate. In other words, over 94% of votes were cast either for elected candidates or the one last defeated candidate.

The new Senate is representative of the wide range of views in Australia – and far more so than the House of Representatives, as the table below indicates:

The 18.7% of people who voted for “Others” includes many supporters of small parties who preferenced larger parties ahead of other parties. An example would be a supporter of the Arts Party who preferenced one of the major parties ahead of a party like the Shooters, Fishers and Farmers. It was never the case that all who voted for the smaller parties would preference another smaller party candidate ahead of any of the major parties.

After the final Senate results were declared, Labor leader Bill Shorten said:

The presence in such numbers of One Nation in the Senate is a direct result of Mr Turnbull and Mr Di Natale’s action in terms of their so-called electoral reform.

There is no evidence that this is so. Pauline Hanson would have been elected under the previous electoral rules; she received more than one quota. The presence of other senators from her party is due to large numbers of people voting for, and giving preferences to, One Nation.

And, under the previous system, One Nation senators may well have been elected because other smaller parties may have preferenced One Nation ahead of other parties.

The vast majority of voters are represented in the Senate by someone they voted for, or directed their preferences to. The table below shows the percentage of votes that contributed to the election of senators in each of the six states:

This table is based at the stage when just one defeated candidate remained in the count: this is the fairest way of calculating these figures.

An even higher percentage of ballots contributed to the election of senators. This is because when a candidate is elected, the votes not needed for their election – the “surplus” – are transferred to the candidate next preferred by the voter, but at a lower vote value (the transfer value).

In South Australia, for example, 269,824 people voted for the ALP above the line and those preferences ended up with the unsuccessful fourth Labor candidate, Anne McEwen. Around 86% of the value of each vote cast for Labor above the line counted to elect the first three candidates, but the remaining 14% of the value of those votes ended up with the unsuccessful last candidate.

Under the previous Senate voting system, all preferences had to be expressed below the line. This meant that, in each of the six states, all 12 senators elected would have a full quota of votes, and at least 12/13 (92.31%) of the votes would contribute to the election of a senator.

So, how did it work this time? Overall, 90.02% of the votes contributed to the election of senators. The difference between that and the 92.31% figure cited above is the extent of exhaustion.

What is exhaustion? Suppose a Tasmanian voted for the following six parties, then left the rest of the ballot paper blank.

1 Citizens Electoral Council

2 Arts Party

3 Voteflux

4 Australian Liberty Alliance

5 Science Party

6 Renewable Energy Party

The candidates for those parties all received few votes and were all excluded from the count early, meaning this Tasmanian voter’s ballot became exhausted, as it indicated no further preferences and thus could not further influence the result.

Much more typically, exhausted ballots come at the end of the count. In Tasmania, for example, 29.5% of all the exhausted ballots were from the surplus of Liberal candidate David Bushby. At the point in the count when his surplus was distributed, three candidates remained: Catryna Bilyk (Labor), Nick McKim (Greens) and Kate McCulloch (One Nation). The value of Bushby’s suplus was distributed as follows:

Surely it is no surprise that 2,816 of those Liberal supporters had no desire to support any of the three remaining candidates. Voters made deliberate choices either to express preferences or not, according to what they believe.

Another important feature of this Senate election, which has not happened for at least 60 years, was the election of a candidate out of order on their party’s ticket. Despite being listed sixth, Labor’s Lisa Singh was elected ahead of the fourth candidate down the column, Catryna Bilyk. The fifth candidate on the ticket, John Short, was unsuccessful. That happened because 26.8% of Labor voters marked their votes below the line, and 18.2% of those gave their first preference to Singh.

The concerns raised about the changes to the Senate system, and the predictions of loss of representation, did not eventuate. Rather, the new system has worked to produce a house of parliament much more representative of the range and balance of Australians’ political views than the House of Representatives.