Does AV make some votes count more than others?

But, in many ways, your vote alone is not enough. In the days and weeks ahead, you also need to challenge your friends and colleagues who are thinking of voting “Yes”. Ask them why they are voting for it. I bet you none of their arguments will stack up – and you need to take them on.So when they say: “AV will make every vote count”, tell them it won’t. It will actually make some people’s votes -especially those who vote for extremist parties – get counted more than others. [David Cameron arguing against AV in the London Evening Standard].

Is the Prime Minister correct with this line of argument? I don’t believe so. A clue to the argument I’m about to advance that Cameron is incorrect lies in the fact that AV is also referred to Instant Runoff Voting.

In full (i.e. non instant) Runoff Voting, what happens is that if in the first round of voting, no candidate obtains a majority of the vote, the lowest placed candidate is eliminated and another round of voting occurs. This process repeats until a candidate obtains more than 50% of the vote.

AV/Instant Runoff Voting aims to approximate this process by replacing multiple rounds of voting with multiple rounds of counting. If you assume that voters who voted for a candidate in an earlier round will vote for the same candidate in later rounds unless that candidate is eliminated and that voters for eliminated candidates will redistribute votes according to their preferences, then by asking at the outset what those preferences are, and then performing multiple rounds of counting until a majority winner is found, you can eliminate the need for several rounds of voting but can still retain the essential point of Runoff Voting, namely trying to achieve majority support for the winner (admittedly the majority is only of those votes making it through to the final round).

Note that in full Runoff Voting, every voter gets a chance to vote in every round, and all votes count equally in each round of voting. By comparison, under AV, every voter gets a chance for their vote to count in each round (by stating their preferences should their preferred candidates get eliminated) and each vote counts equally in each round of counting, it’s just that some votes are first preference and some votes are later preferences, just as is the case under Runoff Voting.

Cameron’s argument implicitly ignores the fact that the votes obtained for a candidate on first preference in the first round get carried through to the next round unless and until that candidate is eliminated, which is the equivalent of voters sticking with the same candidate through multiple rounds in run-off voting. These votes are in fact counted once in each round just like every other vote is.

It thus seems to me that the argument Cameron advances is flawed, equivalent to claiming that full Runoff Voting makes the votes for the lowest placed candidates count more than higher placed candidates when it clearly doesn’t. Each round of voting/counting treats each vote equally under both systems.

The main thing missing from AV that you get in full Runoff Voting is actually the opportunity for voters to change their minds from round to round, i.e. vote for A in round one, but for B in round 2 despite A still being in the running. Runoff Voting thus allows voters to alter their preferences from round to round, but this opportunity is not available either in AV or FPTP, so is irrelevant to making a choice between AV and FPTP.

Will Alternative Vote lead to more coalitions?

British Prime Minister David Cameron claims that Alternative Vote (AV) could lead to coalition governments becoming the norm in British politics:

But there’s another argument I want to make – and one, again, you might find surprising coming from a Prime Minister leading the first coalition government since the Second World War: we shouldn’t vote for a system that could make coalitions the norm rather than the exception.

Cameron’s recent speech also claimed that AV would make coalition government much more likely:

The more people see a clear link between the pledges in a manifesto and the action taken in government, the greater the sense of accountability.

And the real, unavoidable truth about AV is that it would damage that chain of accountability…

…because it makes coalitions much, much more likely.

Furthermore, on Have I Got News For You this week, Tory MP Louise Bagshawe (about 16 mins in) claimed we’d end up with coalition governments under AV “every single time”.

The problem with this claim, is that the evidence for AV making coalition more likely than FPTP is inconclusive, but does suggest that a strong 2 party system makes coalition under AV unlikely, whilst under a multi-party system it will still tend to produce a majority for one party, even if coalitions occur more often in such cases. For example,  according to Channel 4′s Fact Check blog:

• Australia has been using AV since 1919 and, according to the IPPR, has only had 2 coalition governments since then (compared to 5 for Britain since 1900, and 12 for Canada since 1900 under FPTP). However it should be noted that this comparison is complicated by the fact that the Australian National Party and Australian Liberal Party have for decades fought general elections under a coalition agreement both in and out of power, but this agreement has operated to such an extent that they’re effectively treated as one party for general elections. If you treat them as 2 separate parties, then they had coalition governments from 1949 to 1972, plus after the 1980, 1998, 2001 and 2010 elections. Whilst this amounts to a sizeable period of coalition government, it’s not the norm, not as much as you’d get with PR, and certainly isn’t a coalition “every single time”. Also, it’s not clear whether FPTP would have led to fewer coalitions under circumstances where you have a multi-party system with 2 parties having such an entrenched agreement — they could equally have had a pact not to oppose each other in constituencies where this would “split the vote”.  It does suggest that coalitions and even long-running cross-party agreements may become quite common under AV when voters move decisively away from voting for one of two big parties, but then consider how often Britain had national governments and cross-party agreements in the 1920s and 1930s when the Liberals were split and in decline but Labour had yet to decisively supplant them — that was all under FPTP.
• The British Election Survey(BES) has run simulations of how British general elections would have turned out under AV since 1983, assuming voters preferences were the same as they were at each election. Only in 2010 does a coalition government definitely result (and we know FPTP delivered one then), though possibly we might have had one in 1992.

Of course assessing the likely outcome of switch to AV is inherently speculative, e.g.  the BES assumes voters preferences would be unchanged under AV, whilst Australia has a different political culture to that of Britain and the form of AV used there is different to that proposed for Britain making extrapolation from their experience rather uncertain.

It’s worth noting though that much speculation that we’ll end up with hung parliaments rests on the idea that the Lib Dems will benefit by being the second preference of both Labour and Tory voters, however given their rapid drop in the polls since forming the coalition with the Tories in 2010, that does not seem a safe bet anymore. Furthermore, under the projections of the BES, where the Lib Dems were often a second preference,  the Lib Dems did gain more seats but coalition rarely resulted partly because, in the simulation, AV actually increased the government’s majority in landslide elections such as that of 1987, 1997 and 2001.

In the end, given that AV will not produce a proportional outcome, and can result in amplified majorities in landslide elections in a similar manner to the way FPTP does, it seems to me that it is unlikely to make coalition government the norm, but it is possible it’ll make coalition occur more often if voters continue to vote in sizeable numbers for parties other than the 2 main parties. It’s hard to say whether FPTP would avoid coalition in such circumstances.

So what difference would Alternative Vote make?

On May 5th, voters in Britain will vote in a referendum to choose between sticking with the existing First Past The Post (FPTP) voting system or switch to using the Alternative Vote(AV).

Under the AV system being proposed, you vote by ranking the candidates in order of preference, and you’ll be able to rank as few or as many of the candidates you like. So, in a constituency where the Tories, Labour, Greens and Lib Dems were standing, a voter could put their first preference for say the Green Party candidate, their second for the Lib Dem candidate and ignore the Tory and Labour candidate.  When votes are counted, one or more rounds of counting are required:

• First of all the first preference votes are counted. If a candidate receives a majority of votes then that candidate wins.
• Otherwise, the lowest placed candidate is eliminated and their votes restributed according to the second preference for a second round of counting. This process repeats until a candidate receives a majority of the votes for a given round.
• Should someone who’s candidate has been eliminated not have expressed a preference to allow redistribution in a given round, their vote gets eliminated in that round.

The aim is to try and ensure that the winning candidate has over 50% of the votes cast, but in practice this can only be guaranteed if every voter gives a preference to every candidate. Australian elections often require this but the proposed British system will not. Thus it will be possible for someone to win without a majority of all votes cast. An extreme example is if all voters only give a first preference then a mere plurality of first preferences will suffice. More probable is someone’s first and second preference candidates being eliminated and their vote being set aside.

Nevertheless it can  be argued that AV gives the following advantages over FPTP:

• Only those who get a large majority of first preference votes can consider their seats “safe”.
• Voters can vote for their favourite party on the first preference and use their second preference to avoid “splitting the vote’. E.g. a UKIP voter could vote UKIP for first preference with the Tory candidate as a second preference to ensure Labour don’t get in, where under FPTP they might let Labour in by voting UKIP rather than Tory.
• Would-be MPs would need to broaden their appeal since simply obtaining a purality of first preference votes is unlikely to be sufficient to win, they will need to campaign for second and third preferences. This would reward MPs who develop strong constituency backing beyond their party boundaries and thus encourage more independence of MPs from parties.

For these reasons, I believe AV will be an improvement over FPTP and will give voters more power over the final outcome.

However it can be argued that AV might not really make much difference, for example John Curtice argues that the following points suggest AV might not make much difference:

• most of the time people are likely to put their first preference down as the same party they would previously have marked X against.
• even where 2nd and subsequent preferences are counted, because only the preferences of the lowest place parties are redistributed, there’s a limit on the impact of such redistribution. E.g. the two most popular candidates get 70% of first preferences between them, that only leaves 30% for redistribution.
• in the end AV is not proportional and will still tend to reward large parties as FPTP does.

Whilst in the short-run, the impact may be modest, I think this underestimates the long-run impact of a switch to AV for two reasons:

• Curtice bases much of his argument on studies of voter behaviour in mock AV elections. However as voters get used to how AV works they may well alter their behaviour, making more effective use of the second and subsequent preferences over time. Extrapolating behaviour from voters in mock exercises does not cater for this possibility.
• The incentives for politicians will change, they will have to appeal to a broader range of their constituents than before in order to win and keep winning. They will also be disincentivised from attacking a section of their electorate lest they need the second preferences to win.

Thus, I think AV will lead to a long term evolutionary change in how British elections are fought towards more broad based appeals and less divisive politics, albeit still within a majoritarian framework where large blocks of MPs form a government after each election.

That said, AV does have many flaws, e.g.:

• It’s only the second and subsequent preferences of eliminated candidates that get taken into account in each round and the second and subsequent preferences of the two most popular candidates on first preference will only rarely get used.
• It is also quite possible that a larger majority would exist for e.g. the candidate placed first on first preferences if you took all second preferences into account than for the eventual winner.
• Finally, tactical voting is not eliminated under AV, where there may be occasions where it makes sense to put your first preference tactically against a party in order to increase the chances of defeating your least favoured party or even to increase the chances of your favoured party winning. That said, it’s difficult to predict how such tactical voting will work out in practice and there’s less need of it under AV than under FPTP.