As the row over electoral reform becomes increasingly nasty, Chris Game looks at some of the myths surrounding the debate on AV.

Oh dear! It was supposed to be so very different. A referendum on a proportional alternative voting system for the House of Commons, promised the manifesto.

Probably the one chance in my lifetime for ordinary voters to change fundamentally how we do politics in Britain. An informed public debate about genuinely differing ways of electing MPs, organising Parliament, and making policy.

Instead, we have a bad-tempered, personality-dominated, celebrity-driven, seriously deceitful, voter-insulting slanging match.

Whatever the outcome, we surely deserved better. And I do believe it might have been better, had that quoted manifesto pledge been honoured.

It came, in fact, from New Labour in 1997, with the emphasis firmly on that word “proportional”. An independent commission would recommend a more proportional system than First-Past-the-Post (FPTP), and we would choose between the two in a referendum.

The 1998 commission, chaired by Lord Jenkins, proposed a mixed system, similar to those that will be used on May 5 to elect the Scottish Parliament and Welsh Assembly. It was called Alternative Vote Plus (AV+).

Most MPs would still be elected from single-member constituencies, but by the Alternative Vote, enabling voters to rank candidates in order of preference.

But the crucial Plus, that made Jenkins’ system entirely different from straight AV, was that voters would have a second vote, for a party – actually for a regional list of candidates selected by each party. About a sixth of MPs would be elected as ‘Top-up’ members from those lists, in a way that would correct some of the imbalance between votes and seats produced by both FPTP and AV.

AV+ was far from fully proportional. But in 1997, for example, instead of Labour’s 43% vote giving the party 419 MPs (64%) and a hugely inflated Commons majority of 179, AV+ would have resulted in 368 MPs and a still substantial but, Jenkins argued, democratically healthier Government majority of 77.

Of course, the manifesto pledge was broken, and the referendum forgotten.

Labour ministers decided FPTP, much criticised when delivering four successive Tory Governments, was now not so bad after all, and they no longer cared what we thought. Our loss, but also the country’s.

AV+ was carefully designed to fit Britain’s party and parliamentary politics. It could have changed both significantly, which is why I believe the campaign debate would have been more elevated and enlightening than that over AV – which represents about the smallest electoral change possible.

Both campaigns use this reality for their respective purposes. Pro-AV: it’s simple to understand, keeps single-member constituencies, nothing to be scared of. Anti-AV: so little change, why bother?

Which, being charitable, perhaps accounts for the profusion of deceitful and irritating assertions, the following being just a few of my personal unfavourites.

* AV will cost the country £250 million (anti-AV campaign)
The biggest calculated untruth of all. The NO2AV campaign may get ticked off by the Electoral Commission when it’s all too late, but the grossest fabrications are £130 million for electronic counting machines that aren’t necessary and that no one has ordered, and £91 million for the referendum that is happening anyway, on the day already scheduled for regional and local elections.

* AV gives some voters extra votes (anti-AV campaign)
Deliberately misleading. Everyone’s vote has exactly the same value. Multiple preferences are not multiple votes.

In the first count, everyone’s first preference counts as one vote. If a second count is needed and your favoured candidate is still in the race, your first preference still counts for one vote. If your candidate was eliminated, your first preference now counts for zero, but your second preference, if you used it, counts for one vote. At each successive stage, only one vote from each ballot paper is counted.

* Under AV the loser can win (anti-AV poster campaign)
Cynical and intelligence-insulting. In a two-candidate contest – like the boxing match in the poster, and other two-team analogies – the loser, with necessarily less than 50% of the vote, cannot possibly win.

In a multi-candidate contest, the second-placed candidate – virtually never the third-placed – after the first count can win, because in the final count he or she is the most preferred candidate across the constituency.

*All MPs would be elected on a majority vote (pro-AV campaign)
Less cynical, but foolishly misleading. AV is technically a majoritarian system. You do need a majority (50% + 1), not just a plurality – the most votes – to be elected, but a majority of the votes remaining in the final count. With AV, far more MPs than the current 210 (32%) would have a majority of the votes cast, but there would be minority winners.

Unlike in most Australian elections – the country with most AV experience – voters need not rank all candidates. Tests suggest most voters will express two or three preferences, but some – we cannot know how many – will vote only for candidates eliminated early in the count. So there will be cases where neither candidate in the final count secures a majority of the total vote.

*AV is a recipe for coalitions (anti-AV campaign)
Wrong. Shortly after David Cameron formed his coalition last May, Labor (yes, NOT Labour) Prime Minister Julia Gillard formed Australia’s first national coalition in 90 years of AV. Australian federal government has been as two-party dominated as Britain’s, and small parties can have a similar struggle: Greens – 12% of the vote, one seat out of 150. Canada’s FPTP system, by contrast, has produced 13 hung parliaments.

FPTP produced our coalition, and hung parliaments – resulting in either coalition or single-party minority government – will increase in future under either system. Each election, fewer of us vote ‘tribally’ for the two main parties: 97% in 1951, 65% in 2010.

More vote for minor parties: 0.6% in 1951; 12% in 2010. More MPs represent Lib Dems and ‘others’: 9 in 1951; 85 today. This is why reformers argue that FPTP, with its two-party bias, no longer works for today’s voters.

* AV will do away with safe seats (pro-AV campaign)
Just silly. The 32% of seats whose MPs did secure 50% of the vote would effectively remain safe. And most of those short of 50% would still win eventually, though they would have to try to attract support beyond their party’s core voters.

A simulation of the 2010 Election calculated that 43 (1 in 15) seats might have changed hands under AV, Lib Dems gaining (89 seats instead of 57) at the expense of both Conservatives and Labour.

It may be, though, that the days of the Lib Dems being most voters’ second preference are over. Worse yet, the other part of the coalition electoral reform deal – reducing parliamentary constituencies from 650 to 600 and equalising their boundaries – could well leave Lib Dems as the heaviest losers.

Averaging several admittedly varying models suggests the Conservatives might lose 17 seats (6%), Labour 18 (7%), and Lib Dems 11 (19%).

This boundary review may help rule out an early General Election, but when it comes, it could be grim indeed for the Lib Dems. No wonder they’d so much prefer their AV with a Plus.

* Chris Game is an honorary senior lecturer, Institute of Local Government Studies, University of Birmingham.