An expanding crossbench and the chances of a hung parliament


I hadn’t been planning to write a substantive blog post for election day – I usually just post an open thread for discussion during the day. But yesterday I had an idea for one more bit of analysis that seems relevant to consider before tonight.

I have heard a few smart people point out that there is a history of a party winning the two-party-preferred vote but losing the election, and that is true. It happened twice in the 1960s, and again in 1990 and 1998. But this also made me think of a theory I have been explaining when asked about the chances of a hung parliament. A hung parliament depends on two factors: the closeness of the result between the major parties, and the size of the crossbench. A tiny crossbench requires a very close result to produce a hung parliament. A much larger crossbench makes a hung parliament more likely.

So I thought I would examine these two interrelated topics: how does the size of the crossbench affect the chances of a hung parliament, and do those increased chances make a “wrong winner” result less possible? I’m defining a “wrong winner” as a major party winning a majority in the House despite losing the two-party-preferred vote, not simply forming government in a hung parliament.

First up, I gathered data since the 1984 election on the number of seats that would have needed to change hands for the newly-elected government to not win a majority, and what uniform swing would have been needed for those seats to change hands, based on the post-election pendulum. I also then calculated the uniform swing needed for enough seats to change hands for the loser of the election (the new opposition) to win a majority. In effect this creates a range within which a hung parliament would have been produced, or the “hung parliament range”.

This chart also shows the number of crossbenchers elected to the House at that election (in brackets after the year), and the national two-party-preferred margin marked in red.

You can see that the national two-party-preferred margin often falls outside of the hung parliament zonw, which implies that a uniform swing that would have changed the national 2PP winner would not have changed the outcome. This is true for all but one election between 1984 and 2007. Only in 1996 did the national two-party-preferred margin fall within the hung parliament range. Incidentally, the 1996 election produced the most crossbenchers of any election prior to 2010.

Since 2010, three out of four elections have produced a hung parliament range that overlaps with the national two-party-preferred margin, and it was just outside the range in 2016.

This suggests that a uniform swing could have created a "wrong winner" result in 1984, 1987, 1993, 2001 or 2004, although 2004 was only just outside of the hung parliament range. Indeed the Labor two-party-preferred vote in 1993 was quite a bit stronger than their seat count, and a uniform swing of just 0.4% would have flipped seven seats and put them into hung parliament, and a uniform swing of just 0.61% would have flipped nine and given the Coalition a majority.

So why the change over the last decade? Well, I think it's largely because the crossbench has grown.

There were five crossbenchers in 1996, but otherwise there were never more than three prior to the 2010 election. Since 2010, we have never had less than five.

I think these first two charts show that there is a relationship between the size of the hung parliament range and the size of the crossbench, but the next scatter plot makes that very clear.

The two elections with the widest hung parliament ranges were 2010 and 2019, in which six crossbenchers had been elected.

In contrast, the only "wrong winner" results in the last half century both took place in a political environment where the House was almost entirely dominated by the major parties, even if both elections were famous for a surge in the minor party vote. Indeed, the two "wrong winner" results in the 1960s took place with no crossbench at all.

We don't know what will happen tonight. It seems unlikely any of the sitting crossbenchers will lose, and there are numerous prospects for crossbench gains. For all I know we could see ten or more crossbenchers in the House. That makes it very likely that the range of two-party-preferred vote figures that would produce a hung parliament would be wider than it has been for a very long time.

That doesn't mean we will have a hung parliament. If Labor wins the two-party-preferred vote comfortably they could well clear that range.

As long as we have a large crossbench, that will structurally change the nature of close results. A major party can win a majority if they win comfortably, but a close election will likely result in a hung parliament. That may not be permanent, but it will likely be with us for quite some time.

We may well not know the outcome of the election when we go to bed tonight, but it seems very unlikely that both a Labor majority and a Coalition majority will remain options at that time. As the major party vote has declined and the crossbench has expanded, the chasm between these two majority options is getting wider, and I think it's very unlikely that enough seats will be in play at the end of tonight to leave both those options open.

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  1. Mr Green will be calling it by 10pm at the latest. For details of seats that will have swung, see everyone else’s predictions.

  2. I realise that I am probably in the wrong forum for this comment and this is not a criticism of what you are stating here, but I do have trouble with the reductionist approach that everything boils down to a 2 Party vote. However, I do understand this is more a forum for understanding the numbers.

    If the polls are to be believed, then this is possibly another signal of the decline of the big two political parties. There would be many times in the past where, given the choice, I would not give any preference to either of the big two. But a preference I must give, if I am to cast a valid vote. I personally think the compulsory preferential voting (CPV) has led to the decline in the big 2 parties and possibly the decline in our faith in politics. The current CPV effectively corrals the alternative and disaffected voter into eventually giving their vote to one of the two major parties. I think this has made both major parties lazy and arrogant, because they really don’t have to work too hard to convince us of their merits of their particular policies, whilst allowing them to focus almost entirely on the negatives.

    Again, if the polls are to be believed we could have a majority government that effective only garners 35 to 38% of the national vote. Is this representative democracy?

  3. All the talk of hung parliaments…

    I remember when Ricky Muir joined the Shooters, he told me he reckoned they were a good shot at winning Morwell in the 2018 state election and holding balance of power. Not sure if he was just operating on optimism, or they had crap polling data. Probably the former.

  4. polling is expensive if done anywhere near professionally. The only two parties that I have known to have actually hired pollsters were ALP and Libs. Most so called polling by other parties is gut feeling by party members and candidates.
    Very few voters will actually tell a candidate they are not voting for them unless they are very committed to a political party. The ordinary man in the street does not get involved. However political candidates assume that because a person has not thrown a brick through the window that they have their support. The other problem with party polling is that the only time it is released
    To more than a few key leaders is when is Thought to be advantageous to the party.
    The polling that we see in the newspapers is conducted by organisations that make their living out of polling for business organisations. eg do you use soap powder brand a or soap powder brand b. This type of commercial polling is there bread and butter and newspaper polls are more like their advertising expenditure. The polling organisations put a lot of effort into getting the results right because that has an impact on their bottom Line in the future. Imagine a salesman trying to persuade a company to use their commercial polling service being able to say we were the only one I’ve got it right in the 2022 Fedral election. It gives the polling organisation Creedence.

  5. I’m not sure that CPV is the main cause of the major parties’ reliance on negative marketing. It seems to have been imported from USA, where it was based on psychology’s recognition that fear of loss is a stronger short term motivator than hope of gain.

    However CPV does devalue voters’ ability to express their preferences and non-preferences, as well as ultimately entrenching the 2 dominant parties. We’d be better off if it was replaced with some sort of optional limited preference voting, along the lines we now have in the Senate.

    However the Senate voting system is a result of the 2 majors trying to stop preference harvesting (which reduced their ability to control the political game), and at present they don’t have that motive to reform the Reps voting system. But if the majors’ primary vote continues to drop it opens the gate for some charismatic populist pop-up party to charge in. That prospect might give the majors enough motivation to introduce optional limited preference voting in the Reps, which would add integrity to our preferences and open politics to engaging with Australia’s overdue policy reform.

  6. The major parties actually had greater control of who was elected under group ticket voting because they had control of their own ATL voters` preferences, often a substantial proportion of the preferences around even after the election of major party candidates, on a candidate by candidate basis. Now they can effectively only advise their voters on a group by group basis for up to 5 other groups, many of whom will not follow that advice because they are now in control of their own ATL preferences.

  7. As the major parties primary vote goes down, the effectiveness of them directing or recommending their surplus preferences to tame independents goes down. And the ability of preference harvesters like the ‘Preference Whisperer’ to round up preferences to one or another of a cluster of relatively rogue independents goes up.

    We’ll see tonight, but the signs are that the majors’ primary vote will continue trending down. So the ground is shifting under the major parties. They’ll either have to change or risk getting caught out.

  8. Who would have thought the crossbench could be as high as 13 or 14 after this election? I don’t think the most optimistic people saw this coming.

    The coalition have allot of work to do to claw back these seats. And it is likely they will take back a few at the next election. Taking them all back in one stroke will almost be impossible.

  9. The time has arrived where more individuals will have a big part to play in the worn out political system in the country, that career politicians have survived to the detriment of the wider community, populations.

  10. @ Mike Scribbler

    I am a supporter of the optional preferential vote for two main reasons.

    Firstly, it is the more democratic voting option. It allows the voter to truly express the way they want to vote. If I think all candidates are worth some preferencing then yes I will, but there will be other times when I think only 1 or 2 or 3 candidates deserve a preference. If that is how I feel, then that is how I should be allowed to vote.

    Secondly,for some people, being forced to put a number, no matter how low, against a person or party may be morally repugnant. Imagine being a person of colour and having to put a number against a person or party who makes openly racist commentary. I had to hold my nose and put a number against three candidates in my electorate that I find morally repugnant and I get angry that I am forced to do so.

    CVP is just one of the reasons for the decline of the major parties. Would I put it up there as the sole or the top of a number of reasons – no. But I do think it would have been a very interesting result last night if it was run under OPV rules. Labor may have suffered more loses, because my reading of the results was this was not a huge movement towards Labor, but more like a huge movement away from Scott John Morrison.

  11. Hi Ben, just a note – in that crossbench chart, surely the 1975 figure is an error? No Reps crossbenchers were elected in 1975, it looks like it’s confusing it with the Senate (Hall + Harradine).

  12. In response to Neil Flanagan: It is easier for 3rd parties to win seats under CPV than under OPV.

  13. @ Daniel Cotton, please expand on how you see this happening. I am interested to understand.

  14. Hi Neil,

    I think it’s pretty clear that Andrew Wilkie would not have won Dennison in 2010 if the election had been run under OPV. It was a close election where he won from 3rd – the preferences of minor parties really mattered. I think if someone were to carry out an analysis of how often candidates win from 3rd especially (but in general win after being behind on primaries) it will show that they are a better chance under CPV than OPV. In general, when Independents and 3rd parties win (on merit, GVT anomalies don’t count), they turn out to be very good, and their electorate re-elects them more often. So, this is why I’m reluctant to move away from CPV – it produces better outcomes – and does so without distorting the will of the electorate.

    My hypothesis is that this is to do with voter psychology. And there are a number of factors at work:

    1. A lot of voters are lazy. They think about who has a chance of winning, and make a selection out of those. They might preference every candidate they think has a chance, and not bother with the rest. But the thing about 3rd parties and Independents is they don’t get a lot of publicity and their competitiveness is often underestimated. This is especially true in large rural seats where a candidate might be well known in one large town and not elsewhere. So voters sometimes just don’t bother to preference the Independent.

    2. Because you don’t have to order all candidates under OPV, I think people do less research on Independents and 3rd parties. But some people when forced to rank candidates really dislike putting them in the ‘wrong’ order – don’t want to accidentally put an extremist ahead of a decent person. If you don’t have to make a forced choice between them, and you don’t think they’ll win anyway, why bother looking up their platform? But if you look someone up, you might think ‘actually, this person seems pretty good, I might put them ahead of party X’.

    3. Anti-establishment voters and those who resent voting, will often do the bare minimum to cast a legal ballot. They might walk into the booth, and under OPV vote 1 for Legalise Cannabis or One Nation and walk out. But under CPV more of them will probably complete the ballot, adding more Independents and minors before putting all the major parties at the end.

  15. I can see both side of the OPV debate. On one hand, anyone who doesn’t indicate preferences as between the candidates with a real chance of winning is copping out on their democratic duty. On the other, it’s a bit totalitarian to say “If you don’t number every box in a correct sequence we’ll throw your vote into the bin!” (which is what the CPV rules effectively say) – and as Antony Green has pointed out, where one candidate has a majority of first prefs it wastes a lot of the AEC’s time to check that every ballot shows the right number, without skips or repetition, of totally unnecessary numbers.
    So maybe the solution is to copy the new(ish) Senate formality rule – show at least your first 6 preferences (even below the line that’s an effective Senate vote, thanks to the saving provision in s 268A of the Act). Some might still waste their vote giving their 1 to 6 to no-hope candidates, but from everything I’ve read about actual preference distributions (thanks Ben, and Messrs Green, Bowe and Bonham) that is relatively rare – it seems that most voters for a minor candidate then go on to give early preferences to Coalition, Labor or Greens. In some electorates that would change nothing, but in those with 10+ candidates it would be a significant simplification. And having the same rule for Reps and Senate would make it much much easier to explain the system to confused voters.

  16. I agree John, that is also my solution. We act as if we have CPV (or something close to it) but we count like we have OPV.

    The only problem with this is the temptation to advocate ‘just vote 1’. There isn’t much temptation to do that for the Senate, since the electoral system is more complex and it’s hard to predict who would benefit. But in the House it’s usually more predictable (at least it has been until this year) and consistent across most seats, and thus easier to make a strategic decision to sacrifice some preferences to hurt the other side’s preference flows. Ultimately it may be necessary to make it illegal to advocate a ‘1 only’ vote but I am reluctant to do that.

  17. Well, what I didn’t say above was that I wouldn’t have the saving provision (that they have in the Senate) that a “just 1” is formal. I’d be in favour of repealing it in the Senate too – I don’t think it’s terribly onerous to have to write numbers in sequence from 1 to 6 – beyond that it starts to get harder for some and when you get 105 candidates with compulsory prefs it’s onerous for everyone! I know it wouldn’t fully meet Antony’s objection that it puts an unnecessary burden on the officials when there’s a clear winner on first prefs, but at least it would go some of the way. Maybe a saving provision that every ballot with a clear 1,2,3 is formal?

  18. I made the same suggestion of 1-6 in the HoR as a savings provision on twitter yesterday. So, I think we’re all in furious agreement on that point.


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