Referendum opinion polls in Scotland offer contradictory forecasts
Polls show clarity remains an issue even after two years
A Scottish Saltire flag caries a ‘Yes’ for Independence at the Bannockburn Live event last month. Photograph: Peter Macdiarmid/Getty Images
Looking at a mound of opinion poll figures about September’s independence referendum, John Curtice, Scotland’s leading opinion poll expert, displays a dry sense of humour. “Where are we? The answer is we are not quite sure,” he says.
A few things are clear: the gap in the numbers between those who will vote Yes or No has narrowed over the last two years. However, the half-dozen companies that are consistently polling are coming up with significantly different numbers.
For instance, polls from Panelbase – which are paid for by the pro-independence campaign group, Yes Scotland, but which are published widely in Scotland – have consistently found the strongest support for independence.
Since January, it has, on average found that 46 per cent of voters are ready to vote Yes, compared with 45 per cent found by ICM, 44 per cent by Survation, 41 per cent from TNS/BMRB, 40 per cent by YouGov and 38 per cent by Ipsos/Mori.
Last September, Panelbase banned new members from joining the list of internet respondents it tracks to come up with its numbers, following concerns that it had been skewed by Scottish National Party members signing up in droves.
The controversy erupted after Panelbase reported that the Yes side had nudged ahead, by 44 per cent to 43 per cent in the campaign for the first time – just days after YouGov had forecast a 59 per cent-26 per cent No result and TNS-BMRB gave the No side a 47 per cent-25 per cent lead.
Who is wrongSince then, Panelbase has used different panels of voters, but has found similar results to its original figures – while the less optimistic numbers for the Yes side found by TNS, YouGov and Ipsos have continued apace.
“We don’t know who is right and who is wrong. Most polls give the ‘don’t knows’ at about 15 per cent,” says Curtis, who is the professor of politics at Strathclyde University in Glasgow. “That’s not particularly high; House of Commons polls six weeks out from an election are much higher, but people in Scotland have had 40 years to think about this,” he says.
However, longer-term research may offer a better guide. The Scottish Social Attitudes Survey has tracked opinion since the Scottish Parliament was reborn in 1999. Opinions have oscillated over that time, but within relatively narrow bands.
Between 45 and 50 per cent want more devolution, especially over taxation, while the numbers supporting full independence from the rest of the United Kingdom “has consistently been around 30 per cent per cent”, according to a review by the House of Commons Library.