Different versions of the truth ahead of Scotland’s white paper

But “Westminster”, as the “yes” campaign likes to term it (pulling together all UK-wide parties under one label), has already been producing its own version of the truth on independence. There have been eight reports so far, with more to come (Christmas truly is sorted if you have someone with a taste for this sort of thing in the family).

There will be discrepancies galore between the two version of the truth, whether it is on welfare, economic growth, border controls, Nato membership and much else. But two movements can be detected in the “no” campaign line and they are both quite significant. They used to say that Scotland might not get into the EU. Countries like Spain, the argument ran, with secessionist worries of their own, might block Scotland for fear of the precedent.

Now they tend to say Scotland would get into the EU in the end, just not on terms it might like.

The other big change is the hardening up of the line on the currency. You used to hear some “no” camp folk say there might be a sterling currency union with an independent Scotland. That is now heresy. Alistair Carmichael was setting out the line on Marr on Sunday and referring back to George Osborne’s pronouncements when he was promoting one of “Westminster’s” documents on independence earlier this year.

The “no” camp has identified the issue of currency as one that goes to the heart of many voters’ concerns about independence and they intend to add to those worries. The “yes” team argue “Westminster” wouldn’t be so stupid as to cut off its nose to spite its face over a single currency. It needs Scotland’s additions to the balance of payments and wouldn’t want to tip Scotland into any sort of destabilised state with a wobbly currency when it trades so much with its northern neighbour.

Tomorrow is one of the milestone moments in the whole independence debate when both sides get a lot of airtime and print space. Each will want to make headway converting “don’t knows” and firming up support. We’ll soon enough know if either or neither achieved that.

There’s a long section of “questions and answers” in the Scottish government’s white paper. To keep you going before the document drops on this website tomorrow morning at 10am, here’s the answer to a question that you may have noticed often comes up in this long-running debate. Why is Westminster’s estimate of Scotland’s entitlement to North Sea oil smaller than Scotland’s estimate?

The answer is that the land border between Scotland and England might be settled, but the sea border is disputed.

In 1999  the Labour government passed an order changing the maritime boundary from a straight horizontal line out of Berwick to something more curved, sloping 60 miles out to the north and hooking in a few oil wells along the way.

Craig Murray, formerly the British ambassador to Uzbekistan, was also once head of the maritime section of the Foreign and Commonwealth Office. He’s spelt out his thoughts on the re-drawing of the boundary on his blog with a useful map. There’s a more detailed map that shows the oil fields that the line switch gains UK – follow the blue dotted line marked “Scottish Adjacent Waters”. One senior civil servant from that period told me that when the maritime border was redrawn “it is not unreasonable to assume they had nationalism and its case on their minds at the time”.

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