So, it is indeed going to be May 5, as I wrote in breaking the news, last week.

The battle-lines are already being drawn – it is clear that there will be big money behind the campaign to stop change, and retain the status quo. Beside the predictable nonsense from these wreckers, some of ‘the forces of conservatism’ are also (rightly) pointing out some problems with the government’s plans – such as the reduction in seat-numbers, which is liable to be anti-democratic, especially in a country whose population is continuing to rise. But it is important to be clear that, when it actually comes to the referendum, those problems will no longer be relevant. Parliament will decide them one way or another, and the issue that goes to the people to decide on May 5 is simply whether to stick with FPTP or to change to AV. That therefore is the main issue that ought to pre-occupy those concerned with the state of democracy in our kingdom, and with starting to take back Parliament. That is the question on which each of us has to decide: Which side are you on?

There are those who take themselves to be radicals who oppose AV on the grounds of purism: on the grounds that it is not PR. One such is Derek Wall, former Male Principal Speaker of the Green Party.

So, in terms of parties: on the No side are the Conservative Party and Labour tribalists, and maybe some Greens (if the opposition to AV of Derek et al continues). On the Yes side are the Liberal Democrats, Labour pluralists (including Compass, the Millibands and Diane Abbott) and certainly some Greens.

The Green Party will make its decision on where it stands at our Autumn Conference. We are a small party, but it could be an important decision. For, while the Lib Dems and Labour lost seats at this General Election, the Green Party entered Westminster for the first time. There is some momentum behind us, and a lot of respect for our Leader, Caroline Lucas MP.

It seems to me that it would be extremely unfortunate if there were to be a group of ‘PR purists’ opposing AV on the grounds that it isn’t radical enough. The grave danger is that, by dissing AV, such people will give respectable ‘cover’ to those implacably opposed to any reform of our electoral system. Those who will benefit from such ‘purism’ will be Labour tribalists represented by the likes of Prescott, Burnham and Balls, and (above all) the Tories.

That is why I along with several senior elected Greens will be putting the case at a motion at our September Party Conference for supporting AV in the referendum. AV eliminates the wasted vote argument, it largely eliminates tactical voting, it drastically reduces the number of safe seats. It allows the electorate to express their preferences and thus potentially speeds up the process of parliamentary change at a time when Parliament desperately needs to be ready to respond rapidly to environmental change. And it is a start. It is a significant step in the right direction.

To stand in the way of it when the referendum comes will only benefit those such as Lord Ashcroft who are going to put their considerable resources behind the campaign to preserve the present system that has served them so well…

Read more about the AV referendum in OurKingdom's Referendum Plus section.