Brown has put his great clunking feet in it again. If reports on BBC-TV are to be believed, Brown's new National Council on Democratic Renewal - a body that may very well meet mostly in private - is to propose that the UK adopt the alternative vote (AV) for elections to Parliament. There is apparently to be a referendum.

Quite what Brown and his wretched party - I am a former member - hope to achieve is beyond me. There is a very strong group in the party - Mandelson, Hain, Martin Linton, etc, etc - who have long argued the dubious case for AV since they think it is the "electoral reform" option that will best preserve their place in national politics; and since it will block the move towards proportional representation that will alone free Parliament from bondage to the executive. So there is a simple self-serving motive at work. But this is such a stupid gesture that I suspect that they would be happy to put the proposition to a referendum and lose, having falsely demonstrated their commitment to democratic renewal.

So why is this so outlandish? First, because AV is even more disproportionate than first-past-the-post (FPTP). In 1997, we at Democratic Audit - Patrick Dunleavy, Helen Margetts and me - carried out an expert simulation of the actual general election result that year and calculated that AV would have produced a more disproportionate outcome than FPTP - the deviation from proportionality was 23.5 per cent under AV, 21 per cent under FPTP. Labour's bloated seat count would have risen to 436 seats. The Lib Dems would also have benefited disproportionately.

Okay, you may say, this was just a calculation. Well it was impeccably done in the first place. But the actual experience of AV voting for the House of Representatives in Australia has demonstrated time and time again that it produces disproportional results. (In Australia, the deviation is to some degree mitigated by STV elections to the upper house. For more detail, see Democratic Audit's report)

Second, Blair commissioned a report from Lord Jenkins that recommended a combination of AV with a limited numbers of top-up seats, known as AV Plus that would have made it more proportional. Reformers have recently been combining around this option as a compromise. Brown, Mandelson and co have rejected this course.

Third, the public deserve a wider and more deliberative choice than this cynical gesture offers. New Zealand had two referendums around an expert appraisal of all the alternatives, which gave people time to decide in principle to consider change, and then offered them an informed choice between FPTP and a proportional system. (Again, for more detail, see the Democratic Audit's report)

Fourth, the whole proposal smacks of the old discredited politics that disgusts the public. The New Zealand appraisal was carried out by an appointed commission. Here a citizens assembly could do it.

Fifth, it is bad politics. It looks like the desperate self-serving gamble that it is. It gives the Conservatives, who are very anxious about demands for electoral reform, a sitting duck to shoot dead. They have already taken the predictable line - Brown is scared that he will lose under the current system. Amazingly, a Lib Dem MP floundered on BBC News, failing to state that AV is more disproportional than FPTP, even when prompted several times to do so by the interviewer. It is not often that I shout at the telly. But I did out so of sheer frustration. Surely the Lib Dems could have found someone who could make the case for real reform robustly - it is after all the key Lib Dem issue - rather than this vapid ignoramus?

There are other reports - one that Brown may go for an elected second chamber. Go for it, but with a more sensitive form of PR than the rigid system used for the Euro elections!