Alex Salmond's chosen question for the Scottish independence referendum ("Do you agree that Scotland should be an independent country?) is clearly a leading one. As Robert Cialdini, an American psychologist with no stake in the race, told the Today programme: "it sends people down a particular cognitive chute designed to locate agreements rather than disagreements." But would it actually make any difference to the outcome? Lord Ashcroft's latest poll attempts to answer this question. The former deputy Conservative chairman divided the sample size of 3,090 into three and asked several possible versions of the question.
Presented with Salmond's preferred wording, 41 per cent of Scots supported independence, with 59 per cent opposed. Offered a slightly modified version ("Do you agree or disagree that Scotland should be an independent country?"), the number who favour independence falls to 39 per cent and the number who oppose it rises to 61 per cent. As Ashcroft notes, this represents a "four-point difference in the margin between union and independence."
His third and final question asks "Should Scotland become an independent country, or should it remain part of the United Kingdom?" This version sees support for independence plummet to just 33 per cent and opposition increase to 67 per cent. Thus, we now have significant psephological evidence that the wording of the question could determine the outcome of the referendum.
So far, Salmond, who has conceded that the UK Electoral Commission should run the referendum, has said that the commission will have "a role in assessing the questions" but has refused to say whether it would have a veto over the final wording. However, after Ashcroft's poll he will be under even greater pressure to do so.