If Welsh Labour wants a two-member-constituency voting system, this is the one they should adopt

In the recent row over possible changes to the voting system used for elections to the Welsh Assembly, one of the alternatives proposed by the Labour Party was a system of two-member-constituency First Past the Post (see the Devolution Matters blog for an overview of the row). In other words, to expand the number of Assembly Members (AMs) to 80 from the present total of 60 (made up of 40 constituency AMs and 20 top-up regional AMs under the proportional AMS voting system), Labour was proposing having two AMs per constituency and using FPTP to elect them.

Presumably, the model of FPTP they had in mind was that voters would get two votes each, thereby ensuring that where Labour was the most popular party, it would be guaranteed to win both seats even if it were not the choice of a majority of voters. Labour is not known for its enthusiastic backing for fair voting systems, after all. FPTP wouldn’t be so bad if people had only one vote, so that the Labour vote would be split between both candidates, giving other parties more of a chance, especially if they fielded only a single candidate in constituencies where they knew they had no hope of winning both seats.

However, a fairer, more rational and more proportional electoral system for two-member constituencies would be the following, which I’m calling ‘TMPR2’: Two-Member Proportional Represenation (version two). This is a simpler and more practical version of the TMPR system I have previously discussed. TMPR2 works as follows:

  • There are two representatives (AMs, MPs, etc.) per constituency
  • Each voter has two votes. Voters are not obliged to use both votes: they can vote for just one candidate if they wish
  • The individual candidate obtaining the most votes automatically wins one of the seats
  • The individual winner may be either the representative of a party or an independent
  • In addition, if any independent candidate wins the second-highest total of individual votes, that independent candidate is elected
  • However, assuming the second-highest total of votes is not won by an independent, the winner of the second seat is decided on the basis of the share of the vote won by each party:
    • If any party wins over 50% of all votes (that is, the number of actual votes cast, which is higher than the number of voters, as people can vote for two candidates), then both of their candidates are elected (unless one of the candidates obtaining the highest or second-highest total of votes is an independent, in which case the party obtaining over 50% of the vote wins only one seat)
    • In the instance where one of the seats is in fact won by an independent, the party candidate elected is the one that has obtained more votes than the running mate from their own party
    • If, however, no party wins more than 50% of the vote, then the two parties obtaining the highest shares of the vote win one seat each (except in the case where one or more independent candidate are elected, whereby only the top-ranked party or no party respectively wins a seat)
    • In the case that two parties win one seat each, the successful candidates are those who obtained more individual votes than the running mates from their own parties

Advantages of TMPR

  • This is a reasonably proportional system
  • It encourages trans-party voting: voters could and would vote for candidates from different parties. This would equalise the parties’ share of the vote, with the established parties’ share coming down and the smaller parties’ share rising. For instance, quite a lot of right-of-centre voters, if the system were applied in England, would vote for one Conservative and one UKIP candidate; whereas many left-of-centre voters would vote for a Green candidate alongside a Labour or Lib Dem candidate. This means that the vote share parties need to win in order to be elected could be considerably lower than under FPTP. In fact, there is no lower percentage limit on eligibility for a seat. And TMPR2 encourages this pluralism by allowing voters to divide their loyalty between more than one party
  • It incorporates some of the best features of established, familiar voting systems:
    • Like FPTP, the candidate obtaining the largest number of individual votes automatically wins a seat
    • Like AV, if any party wins over 50% of the vote, it takes the whole constituency (i.e. both seats), unless an independent candidate has won either the highest or second-highest individual vote
    • It’s a crude form of PR, similar to STV in the sense that a party, as opposed to an individual candidate, needs to win more than a ‘quota’ of 50% of the vote to win both seats
  • It encourages voting for individuals – and hence, for independents – alongside parties: as voters have two votes each, they will be freer to choose candidates on their individual merits alongside their membership of a particular political party. There would be more of an incentive for independent candidates to run, such as high-profile, respected local figures taking a stand on important issues for the local community
  • It’s easy to understand and operate: there are no complicated voting or counting mechanisms involved, and the result is a clear and direct expression of voters’ preferences. There are no unexpected consequences and fewer tactical-voting constraints for voters. Voters would know that the way they voted would have a direct impact on the result: each of their two votes increases the chances of that individual candidate or party; and if voters are torn between the party / candidate they genuinely prefer and the party they feel they need to vote for in order to ensure that another party does not win (tactical voting), they can hedge their bets and vote both ways.

Disadvantage of TMPR2

TMPR is probably not as proportional as the existing system – AMS – used for elections to the Welsh Assembly and Scottish Parliament. In fact, in an Electoral Reform Society analysis of the 2011 Welsh Assembly election had it been conducted using AMS with 30 constituency seats and 30 regional top-up seats (instead of the present 40/20 ratio) compared with an 80-seat Assembly elected using STV, AMS emerges as the more proportional system. It would be interesting to see the outcome if they ran the same analysis on TMPR2.

However, pure proportionality is not everything; and TMPR does preserve the close links between individual AMs / MPs and relatively small constituencies. By comparison, AMS gives more power to the parties, as top-up AMs / MPs are predominantly elected because of their party affiliation rather than their individual merit or on the basis of local issues. In addition, TMPR is much simpler to understand and operate than either STV or AMS.

Real-world prospects for TMPR2

In reality, TMPR2 has very little chance of ever being implemented, at least not for the Welsh Assembly. As the ‘inventor’ of TMPR2, I don’t exactly have a lot of influence. But as the possibility of two-seat constituencies was being mooted, it seemed timely to bring forward TMPR2 as another alternative: as a possible compromise between FPTP and proportionality. The Labour Party wouldn’t like it, because it’s too fair and proportional. The experts at the Electoral Reform Society probably wouldn’t like it because it’s not proportional enough. But maybe the people would like it if they were offered the choice, precisely because it is fairer than FPTP but less complex and fussy than STV and AMS, with a more transparent link between how people vote in each constituency and the winners.

Anyway, I’m just throwing it out there to see if there are any takers.

English parliament

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If you want a preferential voting system, at least make it preferential

I feel like the kind of pedant that will jump on you for saying ‘less people’, rather than ‘fewer people’; or ‘something I like the sound of’, rather than ‘of which I like the sound’. ‘AV isn’t really a preferential voting system’, I say. Well, yes and no, as it were.

It is the case that, in AV, voters list their candidates ‘in order of preference’. But what does that mean? It doesn’t mean, as you might expect, that if no one’s first preference wins a majority, then everyone’s second preferences will be counted and taken into consideration. Only the second preferences of voters for eliminated candidates are counted, meaning that the second preferences of a majority of voters – i.e. those who voted for the two leading parties – are not even looked at. I don’t know about ‘preferential’; that’s a bit more like giving some voters preferential treatment over others!

So what is needed is a system that treats everyone’s preferences equally. Such a system does exist and is called ‘Bucklin voting‘, which I’ve discussed elsewhere: if there’s no majority on first preferences, every voter’s second preference is counted and added to the candidates’ totals. If there’s still no majority, third preferences are added; and so on till there is a majority for someone (or more than one majority, in which case you take the largest as the winning total) or until the preferences run out and the winner is the candidate with the highest total of votes.

The trouble with Bucklin is that it violates the so-called ‘later no harm’ voting criterion, which says that your lower-preference votes should not be allowed to harm the prospects of your higher-preference votes. For example, if a Tory voter put the Lib Dem candidate down as their second choice, this could help to elect the Lib Dem; whereas if (s)he and other Tory voters hadn’t voted Lib Dem as their second preference, the Tory candidate might have won.

I think you could get over this obstacle by, paradoxically, making it compulsory to list all or at least, say, five candidates in order of preference. Then you could say to voters: ‘Your first preference should be the candidate you most want to win; your second preference should be the candidate you would second-most like to win; and so on until your lowest-ranked candidate is the one you least want to win. The higher you list a candidate in order of preference, the more likely they are to win’. The fact of being forced to select candidates from the most preferred to the least preferred outcome ironically makes it easier to order your preferences ‘sincerely’ without feeling personally responsible for handing the victory to a less preferred candidate. ‘Well, if I have to list five candidates in order of preference, I might as well try and get the best result for myself’.

There would still be tactical voting, but I don’t actually think that’s such a bad thing if tactical voting enables voters to secure a better outcome for themselves. For example, a Tory voter might want to vote for the UKIP candidate as the one they’d second-most want to win. But then, they might think that if they did that, they could let the Labour candidate win (based on the second preferences of Lib Dem and Green voters). So they might decide to put the Lib Dem candidate down as their second choice; and if that candidate won, at least they’d have the satisfaction of having prevented a Labour victory.

It’s a gamble; but almost all single-member voting systems involve an element of that. And at least, this compulsory-ranking version of Bucklin voting allows all voters to put down their actual preferred candidate as No. 1 without fear of wasting their vote; and the tactical vote – if people choose to vote that way – can be reserved for the subsequent preferences. By contrast, it is possible to vote tactically under AV (despite what the Yes camp says), as I’ve discussed elsewhere; but it’s more difficult to work out what to do, and this could paradoxically produce a less satisfactory result for the electorate as a whole.

So the version of the Bucklin system I’m proposing is what AV purports to be – a preferential system – but does it better in that the preferences are all treated equally and so really mean something.

An academic question? Maybe; but like English grammar, I’d rather it was done proper.

Alternative alternative voting systems, part eight: Bucklin voting

So far in this series of articles, I’ve looked at only single member-constituency systems, including AV+, which alleviates the disproportionality of single-member systems by combining AV with a regional-list element (which is what AMS does for FPTP). My discussions have concluded that the Alternative Vote (AV), which is the only voting reform we’re actually being offered, is the least good of all the possible single-member alternatives across a range of criteria.

I would say that, of all the established voting methods I’ve discussed, Approval Voting and score voting (of which my ARV system is an example) are clearly superior to AV in that they give more real choice and power to voters, and the results more accurately reflect the full range of voters’ sympathies. Of the methods I’ve ‘invented’, I would say Two-Member Proportional Voting (TMPR – a compromise between a multi-member-proportional and single-member-preferential system) and Net Voting (a system that resolves the absence of a majority for any candidate on the basis of candidates’ ‘net popularity’, which is the ratio of voters who like them to those who oppose them) stand out as potentially quite exciting alternatives that could really revitalise English and British democracy without going as far as full proportional systems.

In this post and the next, I’ll be discussing two further established single member-constituency systems that rank alongside Approval Voting and score voting as much more satisfactory reforms than AV: Bucklin voting and run-off elections.

For an explanation of how Bucklin voting works, I’ll just quote direct from the summary in Wikipedia: “Voters are allowed rank preference ballots (first, second, third, etc.). In some variants, equal ranking is allowed at some or all ranks. Some variants have a predetermined number of ranks available (usually 2 or 3), while others have unlimited ranks. First choice votes are first counted. If one candidate has a majority, that candidate wins. Otherwise the second choices are added to the first choices. Again, if a candidate with a majority vote is found, the winner is the candidate with the most votes accumulated. Lower rankings are added as needed. A majority is determined based on the number of valid ballots. Since, after the first round, there may be more votes cast than voters, it is possible for more than one candidate to have majority support.”

The version of Bucklin voting I will be discussing is where you’re allowed unlimited rankings (up to the number of actual candidates) but can’t indicate equal rankings.

The main advantage I think Bucklin voting has over AV is that it eliminates the ridiculous situation whereby the second and subsequent preferences of most voters (i.e. those who’ve given the leading parties their first preferences) are not counted and cannot influence the final result, whereas the result can be determined by a relatively small number of second preferences (i.e. those whose first preference was for a minor party). This anomaly means that the winning ‘majority’ under AV can actually be smaller than a latent majority for another party comprising first-preference votes for that party plus the non-counted second preferences. For example, if a Lib Dem candidate was in third place behind Labour and the Conservatives once the votes for all the other parties had been transferred, the Lib Dems cannot win, even though they might have the highest total of first and second preferences combined – because the second preferences of Labour and Tory voters (most of which might be for the Lib Dem) are not counted.

Bucklin voting overcomes these imbalances in AV because, if there is no majority of first preferences for any party, the second preferences of all voters are added, and so on with third and fourth preferences, etc., if required. In practice, in many constituencies, just adding the first and second preferences would be enough to generate a majority for one or more candidates, so you don’t need to go any further – which makes Bucklin voting much simpler, more straightforward and easier to count as well as being fairer.

So, for the above reasons, I would award Bucklin voting three points out of five against the criterion Does every vote count, and is every vote counted?, compared with two out of five for AV. There still would be a lot of preferences that wouldn’t count for anything in a Bucklin election: after the second or third preference, there would hardly ever be any point in voters listing further preferences as the result would already have been determined, and this could mean that genuinely ‘popular’ parties who gained a large number of, say, third and fourth preferences could end up being passed over by the system. Plus, as a single-member system, Bucklin is not particularly proportional, so a lot of voters’ preferences would not help to determine the final result.

On proportionality, my second criterion, I would still award Bucklin three out of five, because it’s clearly better than AV, which scores two. It’s better because it provides a more accurate reflection of the range of preferences of all voters. In particular, in England, the Lib Dems would probably have performed much more strongly in 2010 if the election had been held using Bucklin voting compared with AV, which would barely have improved their performance over FPTP. (According to the Electoral Calculus, the Lib Dems would have won 88 seats under AV based on their vote share in 2010, compared with 57 under FPTP. Using Bucklin, I’m sure their seats tally would have been considerably higher.) This under-performance under AV is for the reason I outlined above: the Lib Dems were the leading second preference of most voters in 2010, but under AV, in many seats, the vast majority of those second preferences would not have been counted. In Bucklin, they are. Have the Lib Dems been misled by the advocates of AV (such as those in the Electoral Reform Society or the Labour Party) into thinking AV is the best compromise for them between FPTP and STV, whereas Bucklin voting would be much fairer and more favourable to them, if they’d had but the wit to look into it?

As for my third criterion, Does the system foster accountability?, I would say Bucklin voting performs at least as well as AV, if not better. So I’m awarding it three out of five. Under Bucklin, winning parties definitely need to solicit the support of voters for other parties because they need their second preferences to be sure of winning. This means, though, that Bucklin would encourage a drift to the centre of the political spectrum as the leading parties competed for support from each other’s voter base.

The same advantage or disadvantage, depending on your point of view, has been adduced for AV: parties need to court each other’s voters. But I would say that, in AV, this actually means that parties have to broaden their appeal in both directions: towards the centre and towards the more extreme fringes of the political spectrum. This is because, in the AV process, the first votes to be redistributed to the larger parties are those of supporters of minor parties such as UKIP, the BNP and the Greens. Therefore, Labour and the Lib Dems will have to appeal to Green voters as well each other’s supporters; and the Tories will have to appeal to UKIP supporters as well as Lib Dem voters. Hence, AV could bring about more polarisation between left and right wing while at the same time leading to more voter disappointment, because the parties will alter their policies and messages to appeal to the broadest church but will not be able to deliver in a way that satisfies many who’ve supported them.

Bucklin, by contrast, encourages genuine competition for the centre ground, which could bring about more consensus politics. Another way of viewing that, though, is that broadly held opinions that are not shared by the party-political establishment – such as support for leaving the EU or creating an English parliament – would not get a look in as the parties made cosy coalition deals involving policies that had not been supported by a majority or even offered to the electorate. Hence, while Bucklin would make politicians more accountable to voters from across the three main parties, it could allow them to ignore popular demands that they do not want to hear.

On the fourth criterion, Does the voting system allow voters to express the full range of their political and personal preferences, and send a message to politicians?, I would award Bucklin no more than two out five: the same as AV. This is for the reason set out above that, after two or three rounds, there’s no point listing any further preferences. Sure, on the first preference, voters can indicate what, in my article on the 3CV system, I described as their emotional or conviction vote: the party they feel most sympathy for but often would not vote for under FPTP because they can’t win or for other ‘prudential’ reasons. But then, in the second preference, voters will often feel constrained to vote for whichever of the parties that can actually win that they feel able to support to some degree. After that, listing any further preferences would largely be academic. Indeed, you would not want to indicate a preference for any party that might stand a chance of defeating your top-two in a third round of voting.

My fifth criterion is: Does the system mitigate [or perhaps ‘obviate’ would be better] tactical voting? Here, I think Bucklin does slightly better than AV, which is prone to a legion of pernicious tactical-voting conundrums, as my previous two posts have argued (see here and here). So I’d give it three out of five. Under Bucklin, there’s no need to vote tactically with respect to your first preference, because, however you vote, if a party you don’t like wins over 50% of the votes, you could have done nothing to prevent it. Your second preference, however, could well be a tactical choice: voting for your ‘second-best’ choice to defeat the party you don’t want to win. But then again, as a second-preference vote, this is technically your ‘second-favourite’ anyway. By contrast, in AV, owing to the complicated logic of trying to ensure that the right two candidates get into the final run-off, you could often feel forced to put down your tactical vote as your ‘first preference’; for instance, in one of the scenarios I’ve described where Tory voters might feel obliged to vote Lib Dem first, rather than Conservative, in order to defeat the Labour candidate.

One other tactical ploy under Bucklin voting could be so-called bullet voting: where supporters of one of the parties in contention to win the seat would not offer any subsequent preferences in order not to harm the prospects of their candidate (e.g. Tory voters not listing a second preference for the Lib Dem candidate in case that helped the Lib Dem to win on second preferences). However, I don’t think there’s anything objectionable about this, and it’s not really tactical voting in the ‘pure’ sense: you could just say it’s voters listing only one choice because they want only one party and no other to win. This could, in any case, equally back-fire on such voters in that, by not voting Lib Dem as their second preference, Tory voters could indirectly help the Labour candidate to win. So voters’ behaviour in this respect is more likely to be shaped by the dynamics in each individual seat rather than being a systemic failing of Bucklin voting.

Finally, How easy is the system for voters to understand, trust and use effectively? Well, much easier than AV, for sure! In fact, I’d say it’s pretty simple and easy to understand: if there’s no majority winner on first preferences, then the second preferences are added (and subsequent preferences if need be) until one is found. It’s much more transparent and obviously fair than AV, as all preferences of all voters are treated equally. Plus it’s easier for voters to work with the system to try and get a result they want, as it’s much easier to predict what the impact of different voting strategies will be: ‘if I put party A ahead of party B as my second preference, will I get my desired result?’ So I’ll give Bucklin four out of five here.

So how does Bucklin shape up in comparison with the other systems I’ve discussed in this series? See the table below for comparison:

Criterion FPTP AV AppV ARV TMPR AV+ NetV 3CV Bucklin
Does every vote count?

3

2

3

4

4

3

4

3

3

Is the system proportional?

1

2

2

3

3

3

3

3

3

Does the system foster accountability?

3

3

4

4

4

4

4

4

3

Does the system let voters express their views?

1

2

3

4

4

3

4

3

2

Does the system mitigate tactical voting?

1

2

2

3

4

2

3

3

3

How user-friendly is the system?

3

2

4

3

3

3

3

3

4

Total scored out of a maximum of 30

12

13

18

21

22

18

21

19

18

So Bucklin performs as well as Approval Voting but less strongly than the score-voting ARV system – but, obviously, much more strongly than AV. Why hasn’t it been considered?

Next time, run-off elections.

Giving second preferences to the Conservatives could be the best tactic for the Lib Dems under AV

If you use the delightful Electoral Calculus to ‘predict’ the 2015 UK general election result using the latest opinion-poll figures from ComRes, there’s very little variation whether you use the First Past the Post (FPTP) or Alternative Vote (AV) electoral systems. According to ComRes, the current voting intentions across the UK would be Labour 40%, Conservative 36% and Lib Dem 10%. Using FPTP without factoring in any tactical-voting swings between the parties, and on the basis of existing constituencies, Labour gains an overall majority of 40 while the Lib Dems drop to only 14 seats. Using AV still gives Labour a majority of 30 but helps the Lib Dems to 32 seats: much better, but still way below the 65 seats that would be proportional to their vote share.

Factoring in a 5% tactical-voting swing from the Conservatives to the Lib Dems doesn’t change the result. However, Electoral Calculus doesn’t allow you to factor in a tactical-voting swing from the Lib Dems to the Tories. On the basis of the Electoral Calculus prediction – however unreliable it may be – I would say that the best thing Lib Dem voters could do to prevent an outright Labour win would be to give their second preferences to the Tory candidates wherever they stand a chance of beating Labour.

This runs slightly contrary to my previous post on AV tactical voting, where I assumed that Lib Dem voters would be reluctant to give their second preferences to the Conservatives in seats of this sort in the context of a Labour resurgence. However, if the aim is to prevent an overall Labour majority, this makes absolute sense – just as it makes sense for Conservative voters to indicate the Lib Dem candidate as a higher preference than the Tory candidate in seats of this sort in order to defeat Labour, on the basis that Lib Dem voters couldn’t be trusted to give the Tories enough second preferences to win. Obviously, if it emerged during the campaign that doing so would be the best means for the Lib Dems to keep out Labour, then the tactical rationale would change.

Ironically, if Labour were thwarted from winning an overall majority by this tactic, then the Lib Dems would be in a much better position to form a coalition with Labour as the largest party. The same tactic would apply under FPTP, except that Lib Dem voters would have only one sensible choice: the Tories. In other words, if Lib Dem voters in Tory-Labour swing seats want a coalition with Labour, they’d be better off voting Tory as their only choice under FPTP, and as their second preference under AV, rather than voting Labour! Such is the bonkers logic of single member-constituency parliaments elected by either system!

If you enter more realistic predictions of the parties’ vote shares in 2015, you get a hung parliament under either system, the only difference being the number of Lib Dem seats. I would consider a 35% share of the vote for both Labour and the Tories to be more realistic, with the Lib Dems recovering to 20%. On this basis, Labour emerges as the largest party under both systems, with the Lib Dems gaining 45 seats under FPTP and 65 under AV.

If you enter lower vote shares for the major parties – on the basis that AV is supposed to encourage voters to opt for minor parties as their first preference – there’s virtually no change to this picture. Assuming a 32% share of first preferences for both Labour and the Tories, and 16% for the Lib Dems, Labour is still the largest party and the Lib Dems win 63 seats. Minor parties pick up only one seat, and that’s not Caroline Lucas for the Greens in Brighton Pavilion, who is predicted to lose her seat to Labour. So much for AV fostering political pluralism!

Tactical voting scenarios under AV

A common argument in favour of the Alternative Vote (AV) voting system that is the object of the planned referendum on 5 May this year is that it eliminates tactical voting. For instance, in a blog post in yesterday’s New Statesman, George Eaton argues that Tory supporters who voted tactically for the Lib Dem candidate in Thursday’s Oldham East and Saddleworth by-election would not have felt pressurised to do so under AV: “Had the Alternative Vote been used last night, Tory supporters would have been free to vote for the Conservatives as their first preference, safe in the knowledge that their second preference votes would be redistributed to the Lib Dems”.

On the contrary, under AV, there would still have been a strong tactical case for Conservative voters to indicate the Lib Dem candidate as a higher preference than the Tory. This would be to ensure that the Lib Dem candidate, not the Tory, would enter the final run-off against the Labour candidate, because the Lib Dem would gain more Conservative second preferences than vice-versa. According to a survey referred to by one commentator on today’s BBC Radio Four Week In Politics show, around 80% of Tory voters are prepared to back a coalition candidate if they stand a strong chance of winning, while only 50% of Lib Dem voters are prepared to return the compliment. So, in the hypothetical Oldham poll held using AV, if the Lib Dem had been in second place once all the votes except those of Tory voters had been transferred, he would have been in a position to win; whereas if the Tory was in second place, there would almost certainly not be enough Lib Dem voters who would give him their second-preference votes to enable him to win.

There are likely to be many tactical-voting scenarios like this if AV replaces FPTP as the electoral system for UK-parliamentary elections. The key to these tactics as a voter is to consider whether you want your No. 1 preferred candidate to win at all costs, or whether it’s more important for you to try to ensure the defeat of another candidate. If the latter is the case, you need to work out which party would be best placed to beat the party you dislike in a final run-off, i.e. in the final count between two candidates once all the second preferences of voters for other parties have been redistributed. You then need to indicate that party as a higher preference than any other party that stands a chance of being in the final two, including your actual favourite party if that is the case.

It’s impossible to predict how the main English parties will be faring when it comes to the next UK general election, in 2015. The scenarios here assume that the coalition government remains in place until then, and that it is stated during the election that it will be re-formed if there is another hung parliament and the parties’ shares of the seats allow them to put together another deal to work together. I then examine the different tactics that might be required by supporters of different parties if the coalition is popular, and the Tories and Lib Dems are resurgent in the opinion polls, or if it is unpopular and Labour is resurgent.

General context

Type of seat

Tactical voting strategy

Reason

The coalition is popular Seat in North of England, Midlands or London that the Tories aim to hold or regain, and where Labour is perceived as the main challenger Labour voters should vote Lib Dem as a higher preference than Labour If the final run-off is between the Tory and Labour candidates, Labour cannot rely on enough Lib Dem second preferences to win. However, if the final run-off is between Tory and Lib Dem, there will be enough Labour voters giving their second preferences to the Lib Dem to defeat the Tory.
The coalition is unpopular Seat in North of England, Midlands or London that Labour aims to hold or regain, and where the Tories are perceived as the main challenger Tory voters should vote Lib Dem as a higher preference than Conservative If the final run-off is between the Tory and Labour candidates, the Conservatives cannot rely on enough Lib Dem second preferences to win. However, if the final run-off is between Labour and Lib Dem, there could be enough Tory voters giving their second preferences to the Lib Dem to defeat the Labour candidate.
The coalition is popular or unpopular Seat in North of England, Midlands or London that the Lib Dems aim to hold or win, where Labour is perceived as the main challenger (e.g. Oldham East and Saddleworth) Tory voters should vote Lib Dem as a higher preference than Conservative If the final run-off is between the Tory and Labour candidates, the Conservatives cannot rely on enough Lib Dem second preferences to win. However, if the final run-off is between Labour and Lib Dem, there could be enough Tory voters giving their second preferences to the Lib Dem to defeat the Labour candidate.
The coalition is unpopular Seat in South of England that the Conservatives aim to hold, where the Lib Dems are perceived as the main challenger Lib Dem voters should vote Labour as a higher preference than Lib Dem If the final run-off is between the Tory and Lib Dem candidates, the Lib Dems cannot rely on enough Labour second preferences to win. However, if the final run-off is between the Conservatives and Labour, there could be enough Lib Dem voters prepared to give Labour their second preferences to allow Labour to win.
The coalition is popular Three-way marginals Labour voters should vote Lib Dem as a higher preference than Labour If the final run-off is between the Tory and Labour candidates, Labour cannot rely on enough Lib Dem second preferences to win. However, if the final run-off is between Tory and Lib Dem, there will be enough Labour voters giving their second preferences to the Lib Dem to defeat the Tory.
The coalition is unpopular Three-way marginals Tory voters should vote Lib Dem as a higher preference than Conservative If the final run-off is between the Tory and Labour candidates, the Conservatives cannot rely on enough Lib Dem second preferences to win. However, if the final run-off is between Labour and Lib Dem, there could be enough Tory voters giving their second preferences to the Lib Dem to defeat the Labour candidate.

Clearly, these examples of tactical-voting scenarios are hypothetical, and as we have not yet had an election using AV, we don’t know if these strategies would work out in practice. But they are logical even if so counter-intuitive that many voters may not appreciate the opportunities that exist to vote tactically under AV and so obtain what they would regard as a more satisfactory result. But I hope at least to have demonstrated that AV is far from eliminating tactical voting: it just makes it more difficult for voters to use to their advantage.