Take AV seriously: it has advantages over PR

You don't get far in a discussion of the merits of AV before somebody says 'AV is nobody's first choice; it's not even very proportional'. We seem incapable of escaping the proportional vs majoritarian plane when what we should really be discussing is consensus vs minority rule. AV's greatest merit is that its incentivises campaigns, policy and government that appeal to the consensus.

And in case anyone's in any doubt about the value of consensus, consider the full horror of what the Conservatives indicated they would do with an absolute majority: the proposal to cut inheritance tax illustrates my point perfectly. It constitutes an electoral bribe for nine million of the wealthiest people in Britain. It appeals to a section of society at the expense of another – it would have to be offset by further austerity measures. Thank God for compromise then! A huge social injustice was avoided by the need to form a coalition – to reach a consensus with coalition partners.

PR may achieve consensus government, but too often the price is a rainbow coalition, with small parties (with next to no mandate) having the power to bring down a government. AV may not allow proportional representation of small parties, but that is a strength. Any coalitions resulting from an election under AV would consist of two or three medium-to-large parties. That's a scenario where equal partnership in a coalition is reasonably faithful to the popular vote. Conversely, for a party receiving 5% of the vote to be an equal partner is undemocratic, and that's a risk with PR, which is solved by AV.

But AV, almost uniquely, has the merit of incentivising consensus, not just in the smoke-filled rooms, but on the campaign trail. Parties will be forced to compete with each other for vital second and third preferences. Parties will be forced to make and enact policy that is palatable to all sections of society. This prediction might be contested. Perhaps it is the case that Tories could ignore the poorest 20% and still achieve a majority solely from constituencies in the rural heartlands. Even if this were possible, it would still make it much harder to win key constituencies if they had alienated a group of the voters (key constituencies are by and large more diverse in social make-up). AV will mean parties have to find manifestations of their ideologies which do not alienate any part of society.

But perhaps most undiscussed is the question: how democratic is a system where politicians run divisive campaigns, only to coalesce cosily the day after the election? Why is it that finding the consensus must be done in the smoke-filled rooms? UK election campaigns invariably have the unsaid tagline 'vote for us to stop them getting in'. If we are to see more coalitions, this is unsustainable. It's a sham with which voters will soon become angry and disillusioned. And yet PR promises to bring no less of this sham than FPTP.

AV, on the other hand, means that what voters are presented with on the doorstep is a representation of the consensus to come. Let the people decide where the consensus lies. An AV-elected majority government will have had to have run a consensus-based campaign; an AV-elected coalition will not have pretended to the people that the parties of which it is comprised were mortal enemies. Even without coalitions, divisive government will be impossible and coalitions will cease to be 'stitch-ups'.

These are the things we need to be discussing. I can't see why anyone who is opposed to divisive minority governments (and surely every liberal is) could vote against AV. AV is my first choice, because it isn't PR.