Mark Stuart: Battle over ballot reform adds strain to political marriage of convenience

Back then, Nick Clegg realised that he could not persuade David Cameron to agree to his preferred system of the Single Transferable Vote (STV), so they settled on a referendum on AV instead.

In return, Cameron got his wish to cut the number of MPs from 650 to 600. A huge piece of legislation – the Parliamentary Voting System and Constituencies Bill – was therefore pushed through the House of Commons, and against an unwilling House of Lords, in order to satisfy both wings of the coalition.

Whatever the outcome of the referendum in May, real dangers lie ahead for both David Cameron and Nick Clegg.

Should the referendum be lost, then both leaders will be anxious to prevent it from leading to the collapse of the coalition. Cameron has already said he does not want the referendum outcome to become a “coalition breaker”.

I sense Cameron’s discomfort over AV. The whole logic of his position – that a coalition government was needed last year in order to provide stable government – suggests that he should support a “yes” vote in the referendum, but he can’t do that because of his party’s visceral opposition to changing the existing First-Past-the-Post system.

Indeed, Clegg accused Cameron of “talking complete bilge” when he defended the current electoral arrangements at Prime Minister’s Questions last week.

I believe that Cameron will stand above the fray during most of the referendum – international tumult might come to his rescue – and sub-contract the job of the no campaign to political bruisers such as the Justice Secretary Kenneth Clarke, who will trumpet tired old arguments about coalitions leading to instability.

Meanwhile, Nick Clegg’s problems will be far more severe in the event of a “no” vote. At a stroke, one of the key reasons why the Liberal Democrats joined the coalition in the first place will disappear. And I suspect that whenever there is a future policy disagreement with the Conservatives, it will be interpreted by Clegg’s many Left-leaning MPs as a potential excuse to exit from the coalition.

Should the AV referendum be won, then the Tory Right-wing will start to focus its fire even more intensely on David Cameron. For many on the Right, joining a coalition with the Liberal Democrats in the first place was a stomach churning experience; losing their beloved First-Past-The-Post voting system could prove just too much for Conservative MPs to bear.

However, while potential discontent from the Tory Right may threaten the future harmony of the coalition, it is unlikely to affect its durability because of the Government’s large majority in the House of Commons.

What Clegg and Cameron should be more worried about are three potential problems that could flare up in relation to the referendum.

The first relates to its organisation. In their headlong rush to hold the referendum in May, we are asked to believe that two short months is sufficient time for polling stations and ballot papers to be made ready and everything to run smoothly.

Given the ghastly experience during last May’s general election, when returning officers were unable to cope with a modest rise in turnout, I simply doubt the ability of the organisers, especially in Scotland, Wales and Northern Ireland, to hold two different sets of elections – and using two different voting systems – on the same day.

If it all ends in a shambles (as I fear it will), then Nick Clegg must take the blame as the Cabinet Minister responsible for the legislation.

My second fear relates to low turnout. The hope of Clegg is that voters in the three nations of the Union outside England, used to proportional representation and having to vote in the devolved elections anyway on the same day, will turn out in reasonably high numbers in favour of AV. But what about the turnout in England?

Those areas holding local elections might expect to see a turnout of around 30 per cent, but what about London where there are no other elections being held? Can the referendum really be said to have secured the full-hearted consent of the British people if say, only a fifth of Londoners and perhaps one third of the rest of England bothers to vote on May 5?

My final fear about a successful AV vote relates to the unpredictability of the next election. Election experts are cautioning against predicting the outcome of the 2015 election under AV by drawing on the results of the 2010 election based on First-Past-The-Post. The evidence suggests that voters behave very differently according to which voting system is used.

Overall, AV looks set to provide a small net benefit to the Liberal Democrats, while disadvantaging the Conservatives slightly more than Labour, but we simply can’t be sure.

One thing human beings dislike is uncertainty. Given the British people’s innate conservatism, unlike most experts, I’m predicting a “no” vote in May. Both Cameron and Clegg could live with that. Besides, they could then resume the more far important task of putting the economy right. Now to that proposition, I’d vote a resounding “Yes”.

• Mark Stuart is a political analyst and author from York who has written biographies of Douglas Hurd and John Smith