10 votes: C B D A E
9 votes: B A C D E
9 votes: D E C B A
3 votes: A B C D E
2 votes: E D C B A
(C wins FPTP, and is preferred about 2:1 to any other candidate, B wins AV)

Also, of course, if AV’s supporters are claiming the “50% support needed” property for it – which implies in the loose ways it’s generally talked about the Condorcet property rather than the rather more complicated property it actually has – I think it’s fair to point out that AV does not in fact pass the Condorcet criterion [1].

And then of course there’s monotonicity, where FPTP has a clear advantage over AV.
8 votes: A C B
8 votes: B C A
7 votes: C B A
(B wins, but if B convinces two of the ACB voters to vote BAC – an action that makes the electorate as a whole only more favourable to B, then C wins)

The problem with AV is that it only works on average, and the situations in which it doesn’t work it can give some very bizarre results.

I think it’s better than FPTP, certainly, on balance – but I would be extremely surprised if the majority of the electorate would intentionally vote for a non-monotonic voting system because it’s one of the worst properties a voting system can have. That FPTP is so terrible that this major disadvantage of AV still leaves AV ahead … well, I’ll be voting ‘Yes’ in May, but without much enthusiasm.

Fortunately, the No campaign are too busy thinking up implausible lies to worry about unpleasant truths.

[1] When electing a Parliament by multiple single-place elections, I would argue that you want an electoral system that doesn’t meet Condorcet, just so you can have some variety in Parliament. So in that context it’s a strength of AV. I suppose you could argue that non-monotonicity, because it increases unpredictability, is also desirable, but that might be going too far.

Something that can’t readily be described in few words. It requires complex formulations about how votes are worth different things to different people, in different places, and under peculiarly different circumstances. How that complexity is somehow fairer, yet the more one digs into it the more one comes beguiled, then confused, and then disgusted…

It is the end of democracy in Britain, it is the beginning of permanent LibDem dominated coalition government; the floodgates to the slippery slope to a smooth easy patch-in to the EU-superstate.

And what we would actually lose with it? Forever the ability for us to vote out an entire political class or entire political ideology.

It is not a stepping stone to PR. No party will give us that. And certainly not the LibDems.

The LibDems love AV precisely because AV crushes the other small count parties at first count; counter to what the loving public perceive of it.

AV is nothing but the LibDem CUCKOO’s egg in the nest of British democracy.

Very interesting – especially as this looks so plausible as a real-life split between three main parties (= e.g. Con-Lib-Lab 10,000, Lab-Lib-Con 9,000, Lib-Lab-Con 3,000, Lib-Con-Lab 3,000). I suppose this amounts to giving first preferences extra weight; maybe that’s a good thing.

And if we have more situations like after the 2010 election and how the Lib Dems did their about turns, that isn’t exactly giving power to voters is it…

But there are some terrible arguments for AV in this post, which are based on common misconceptions about the properties of AV as an electoral system. (Spot on with the cost argument, though)

“where is the equality in a system – such as the current one – that awards a parliamentary seat to a candidate whose opponents outnumber their supporters.”

A fair question, but:
1) By definition any multi-member PR system will do that; that being the whole point.
2) Even if we restrict ourselves to single-member systems, AV is quite capable of doing that too. Consider the following set of preferences:
10 votes: A B C
9 votes: C B A
3 votes: B C A
3 votes: B A C
Candidate A will win in AV (13-12 over C in round 2), but a majority of voters prefer candidate B to candidate A (15-10)

This would be an argument in favour of Condorcet, not AV.

“what is wrong with having the support of an absolute majority (as opposed to a mere plurality) of voters.”

And it’s not even a majority of voters guaranteed anyway – some initial projections I’ve done suggest that, depending on the way the votes fall, some English seats could see the winner have only 40-45% of the initial votes (though of course over 50% of the remaining transferable votes). The majority would be over 50% of the original, though.

And fully agreed with Ash’s points on the difference between the relative support expressed by AV preferences (A more than B) and the absolute support implied by that sort of statement (perhaps Approval Voting with a threshold would be more suited here?)

“Indeed, the leaders of parties that conduct these negotiations would be far more constrained if they knew – along with the voters themselves – the full range of preferences of the voters who supported them;”

But they’re not going to, not fully. They’ll be able to see how votes were transferred from some candidates in some seats. However:
– in any seat where there’s a first round victory (probably about a third of all seats, to start with) no transfers will be known
– in every other seat, potential transfers from the top two candidates will not be known
– in a seat where a party comes in fourth or fifth (which can even happen to major parties), how many of the third-placed party’s supporters would have transferred to them will again not be known.

After excluding those voters – which will be the majority of a major party’s first preference voters almost by definition – you have to believe that the minority of remaining voters is representative of all voters. I have my doubts. The coalition decision would essentially be made based on the seats in which the deciding party was third (or worse).

(Or you could use opinion polling of second preferences to avoid that problem, but you could do that without AV)

“they should be supporting a system that brings an end to artificially ‘safe’ seats where huge numbers of voters have little chance of affecting election results.”

There are actually relatively few seats which are safe under FPTP that would be meaningfully contested under AV. On the scale of “ultra-marginal, marginal, moderate, safe, ultra-safe” it’s unlikely to move a seat more than one place.

Multi-member PR is the only system that would end safe seats. AV will marginally reduce their numbers (and could make some other seats even safer)

“For electoral reformers, a system is fair if and only if it allocates seats proportionately to votes.”

Huh? Only if you define ‘electoral reformer’ as ‘someone who thinks a system is fair if and only if it allocates seats proportionately to votes’! If you define it (more reasonably) as meaning ‘someone who wants to reform the electoral system’, electoral reformers could support anything from STV to AV+ to AV, or even (say) keeping FPTP in the Commons and having a second chamber based on another system.

Dionyssis

“no MP will be elected without the explicit support of an absolute majority”

To reiterate: I just don’t accept that expressing a preference for candidate A over candidate B amounts to giving candidate A one’s “explicit support”. If pressed, I would have to concede that I prefer sprouts to vomit, but that falls some way short of an explicit expression of support for the inclusion of sprouts among my pizza toppings.

On AV and safe seats, my point concerned artificially ‘safe’ seats, i.e. constituencies where the MP does not actually command the support of an absolute majority of those who have voted. If AV is adopted, no MP will be elected without the explicit support of an absolute majority.

This is directly linked to the second criticism:
“What is wrong with having the support of an absolute majority (as opposed to a mere plurality) of voters.” Well, also ask what is RIGHT about it? The simple and pretty fundamental point that under AV 50%+1 is – as in maths – greater than 50%-1. As a result, the legitimacy of the incumbent is far greater. Again, opponents of AV contradict themselves if they both claim the opposite and that they support the “one person, one vote” principle.

Also, since we are asked to choose between two options (FPTP and AV) it is important to compare them which is what I did when I argued that “AV is much fairer than the current system”. This is so also because politicians who try to form a coalition government (if it comes to that) know as much as the voters on what kind of support they have.

“If the Labour opponents of AV genuinely care for equality of representation, they should be supporting a system that brings an end to artificially ‘safe’ seats…”

AV does not end safe seats. Nor will it necessarily reduce the number of safe seats. As Dr Renwick of Reading University and author of A Guide To Electoral Reform points out: “The biggest problem for YES is that AV won’t significantly change the number of safe seats. Certainly the claim that AV ends safe seats is untrue.”

“What is wrong with having the support of an absolute majority (as opposed to a mere plurality) of voters.” Well, also ask what is RIGHT about it?

Market research finds that “for general elections, voters consider which party they wish to govern the country, and see the election of their local representative MP only as a means to this end. Candidates are generally expected to support policies equivalent to those of the party, so are not regarded as separate entities.”

If the choice of party is the primary voter consideration and the constituency is only a means in which to register this support, then why is it important that a party gets a measure of support from the majority in a constituency? If voters want to have a say in electing a government then the most important factor is that everyone’s first choice counts in determining the composition of Parliament. This requires a proportional system in which each vote counts equally. Both AV and FPP perform equally abysmally in achieving this; there is no reason to prefer AV in this respect. When we focus on the bigger and more important picture of what voters want, the requirement for majority support is neutralized.

“In reality, AV is much fairer than the current system because it enables voters to indicate – only to the extent that they wish to do so – the range of parties they are willing to support thus giving a steer to politicians when they conduct such negotiations, if the election leads to a hung parliament.”

For electoral reformers, a system is fair if and only if it allocates seats proportionately to votes. Under AV most scenarios show that only the LibDems will consistently gain more seats. Will they take account of how many first preferences UKIP get when negotiating foreign policy during negotiations?

We outline the principled case against AV on our website.