I have added a page listing polls on support for Scottish independence here (and linked from the sidebar). It’s a question that produces some wildly differing responses, allowing people to argue that the polls show almost anything they want. It tends to be asked about in at least four different ways, they all show different things and pollsters aren’t consistent over time in what they ask, so it’s hard to pick up a trend. So, what can we tell about the actual state of public opinion?
When respondents are asked to choose from a broad range of options – complete independence, increased powers for the Scottish Parliament, the status quo or the abolition of the Scottish Parliament – we almost always find that complete independence is only the preferred option of somewhere between a quarter and a third of people in Scotland. The favoured option is nearly always to retain the Scottish Parliament but give it increased tax raising powers. This is one instance were the same question can be tracked over time, since it is asked every year in the Scottish Social Attitudes Survey. The most recent figures show 23% of people in favour of independence, 55% in favour of a Parliament with tax raising powers, 8% in favour of the status quo and 10% in favour of the Scottish Parliament being abolished and a return to Westminster rule.
The only question that consistently produces a plurality in favour of Scottish independence is in response to the straightforward question of whether respondents are in favour of Scotland becoming a country independent of the UK. Responses vary over time, but more often than not the balance is in favour of independence.
These have been quite simple questions though – independence or not. Questions that have given respondents more technical or more tightly defined options, asking them to say how they would vote in a referendum to chose between an independent Scotland outside of the United Kingdom, or retaining the Scottish Parliament as it is now, have tended to show a slim overall majority opposed to independence with support for full independence down to around a third.
Two possible explanations for the difference suggest themselves to me. Firstly I suspect that the straightforward “do you support independence” style questions are getting an emotional, gut response driven by patriotism. They are people saying that Scotland is a country in its own right, rather than people thinking about the constitutional arrangements for governing that country. The other possiblity that strikes me is the mention of the Scottish Parliament – in the simpler questions it is a choice between an independent Scotland or some unspecified alternative…when the alternative is spelt out as being the existing Scottish parliament, some respondents are presumably of the view that they are happy with that.
What is the best representation of Scottish opinion? Well in many ways they are just measuing different things – it can be both true that the preferred option is a Parliament with tax-raising powers, but given a forced choice between independence or the status quo people would plump for the latter. In practical terms though public support for Scottish independence is important purely because the day may come when people in Scotland vote on it in a referendum, and since the SNP last year set out what sort of question they would ask in a referendum, we can see what people think about that.
Referendum voting intention polls this far out aren’t particularly reliable – like general election polls they can only tell us how people would vote if there was a referendum tomorrow…and there isn’t. In real life if there was a referendum tomorrow there would have been a couple of weeks of campaigning beforehand and who knows how opinion would have changed once people considered the arguments. For now though, polls using the sort of wording that the SNP have suggested for a referendum show a lead for NO voters, though varying in size between 20 points and a narrow 4 point lead. Given the underlying preference for a beefier Scottish Parliament over full independence, I’m more inclined to believe the former, but who knows what would happen during a campaign.