The Alternative Vote: yes or no?

The vote is a remarkable thing. It is key to a free and fair society. On 5 May 2011, voters have the chance to decide whether to keep the First Past The Post system or replace it with the Alternative Vote — a change that some argue will produce a more progressive and fair political system.

The case for First Past The Post rests on three claims: it is easy to understand; it produces clear winners with a strong mandate to govern; and it avoids post-election horse-trading on policies not put before the electorate. None of these arguments is especially robust under scrutiny. Ranking candidates is no more complicated than placing a single X. Strong majorities produced by FPTP often rest on a very thin share of the actual electorate — in 2005, the Labour government commanded the support of just 21.6% of eligible voters. And governments regularly produce policies not detailed in their manifestos.

The case for the Alternative Vote is more compelling. Under FPTP, 433 of 650 MPs in 2010 were elected on less than 50% of the constituency vote. AV, by requiring candidates to command majority support, would make MPs more representative of their constituents and give them broader appeal to get elected. While AV does not eliminate tactical voting in all circumstances, it does allow voters to express genuine preferences without necessarily wasting their vote on an unviable candidate. And although AV does not produce genuine proportionality, it tends to produce outcomes closer to parties' vote shares than FPTP does.

A vote for AV is also a vote for a different kind of political culture. Coalition governments — more likely under AV — require a more consensual approach, correcting the adversarial pantomime of Westminster. MPs who need broad support to get elected are less likely to run campaigns built on personal attacks.

A recent academic paper found that if AV had been operating in the 2010 general election, the Conservatives, Labour and Liberal Democrats would have won 284, 248 and 89 seats respectively — significantly altering the arithmetic of post-electoral coalition building.

The case for voting Yes on 5 May is not simply about fairer votes. It is about a better political culture.