Leading article: The No campaign is built on fear and cynicism

Earlier this week, David Cameron argued that adopting the Alternative Vote will do "nothing to rebuild trust in politics". It is a dubious contention. The requirement under AV for MPs to have the support of a majority of local voters should strengthen the link between politicians and the general public. But what is likely to be detrimental to trust in politics, however, is the unscrupulous and deeply cynical manner in which the No camp has run its campaign in recent weeks.

AV is certainly not a perfect electoral system. There are decent arguments that can be made against it. AV can enhance majorities in landslides. And it is not a proportional system either. These are not overwhelming arguments against the reform on offer in next month's referendum. The benefits outweigh the drawbacks. And for all its faults, AV is still vastly superior to first-past-the-post. But these are, nevertheless, serious arguments and ought to be at the heart of the debate over the coming weeks.

Yet the No campaign has not bothered itself with any of these points. Instead, it has resorted to cynical scaremongering, in order to frighten the public away from backing reform. The Conservative Party chair Sayeeda Warsi has argued that AV will be a great boost to the British National Party. Coming from a politician who claimed in 2007 that BNP voters have "some very legitimate views" on immigration, the hypocrisy is clear. But more importantly, there is no evidence to support the contention that racist parties such as the BNP would benefit from AV. Indeed, the BNP themselves are urging their supporters to vote No next month.

These claims about the BNP are merely one manifestation of the cynicism of the No campaign. They have produced posters claiming that the cost of moving to AV would be £250m and implying that this money would be better spent on maternity units and body armour for British troops. Again, the hypocrisy sticks in the throat. The biggest supporters of the No campaign are also those who have been most vocal in calling for cuts in public spending.

But this £250m figure is, in any case, spurious. Some £90m of this would be spent on the referendum in any case, and would not be saved in the event of a No vote. And around £130m of that figure is predicated on the assumption that expensive new electronic counting machines would be introduced. The flaw here is that those expensive machines are a figment of the No campaign's imagination: there are no plans to introduce any such technology.

The No campaign has also tried to smear the Yes campaign over its funding. It claims that the Electoral Reform Society, which is supporting the Yes campaign financially, has received millions of pounds of taxpayers' money. This is deeply misleading. A commercial subsidiary of the ERS has been paid by local councils in recent years for printing ballot papers. The No campaign maintains that this creates a conflict of interest. But for that claim to be credible there would have to be big money to be made by the ERS from a switch to AV, which simply is not the case.

The No campaign does not appear to have a very high opinion of the intellectual capabilities of the British public. It presents AV as "complicated". But the public is surely capable of listing candidates in order of preference. This already takes place in some local elections and voters have managed perfectly well. Yet perhaps the greatest insult from the No camp is that it expects the public to swallow its misrepresentations and exaggerations without wondering about the motives of those serving up this propaganda.