Does the Scottish Parliament hold a veto over Brexit?
Does Holyrood hold a veto over Brexit? The UK government would say no. Twice. The Scottish government would say no. Twice. But that is because it does not care to use the word "veto". And indeed has not done so.
Let me explain - inasmuch as one can use such a precise word as "explain" in connection with such a complex and contentious issue as Brexit and its implications.
It strikes me there are two distinct areas where Holyrood is entitled to be consulted with regard to Brexit. These are being cheerfully confused by sundry politicians and commentators.
The first area concerns the negotiations with the European Union which will lead to Britain's departure from the EU. The second concerns the bill which will be tabled to legislate for the return of EU law to the UK.
Let us take these in order. Theresa May, David Mundell and colleagues have all said, repeatedly, that the UK government will negotiate terms for the UK as a whole leaving the EU. It is almost as if they have a rehearsed line on this matter. Which, of course, they do.
UK ministers say that the Scottish government will be involved, will be consulted, will be engaged - perm any one from those three verdicts. But there will be no veto.
However, that characterisation is not accepted in terms by the Scottish government. They want participation, not consultation. They want to help frame the terms of the UK's negotiating package and, where relevant, they want to advance those terms in talks with the EU.
To be clear, they do not describe that as a veto. To repeat, they choose not to use that word. Indeed, Nicola Sturgeon has taken pains to avoid such a description.
She has noted, for example, the view emanating from Wales that the Brexit package should be subject to endorsement not just by the Commons but by all the devolved legislatures in these islands. She adds that there are certain attractions to such an argument - but she herself is not advancing it at this stage.
Why? Three reasons. One, she genuinely wishes to extract as many concessions as possible for Scotland from the UK Brexit process - and sees conciliation as the route.
Two, politically, she calculates that a troubled and anxious public would welcome a note of co-operation - along the lines of the customarily seductive argument: "Why don't they all just sit down and sort it out?"
Three, it rather suits her if direct conflict over this issue between the UKG and the SG is deferred. If she is to call indyref2, she would rather not do it now - while the UK, including Scotland, is in turmoil and the terms of Brexit have yet to emerge in any meaningful way.
But, to repeat, Ms Sturgeon and the Scottish Brexit Minister Mike Russell are looking for far more than is currently on offer in the negotiation process from the UKG.
They were, therefore, exasperated to see the outline process of Brexit pre-emptively announced to the Conservative conference. They griped a little - but calculate that Mrs May requires to unite her party around a future direction: one which consoles Remainers, a little, while assuring Leavers that Britain will do just that. Leave.
So the SG/SNP complaints were mostly confined to social media muttering. For now. Why? See above re the need to sustain a mood of conciliation. So much for Part One.
Enter Part Two. This is the statute which will be necessary to repeal Britain's membership of the EU and to repatriate those laws which are currently dispensed by or shared with the European institutions.
It is described by its advocates as the Great Repeal Bill. Some would dissent from that adjectival choice. Although they would probably accept that alternatives would fail to stir the blood. The Limpid Repeal Bill?
Let us talk, neutrally, of the bill. Would it require to be endorsed by the Scottish Parliament under a Legislative Consent Motion (LCM) - previously known as the Sewel Convention?
The UKG says no - although not all that assertively and not all that loudly. Their argument is that the bill would be concerned solely with foreign affairs and the constitution. Both those issues are reserved to Westminster. QED.
Except, says Mike Russell, the said legislation would impact directly upon areas which are explicitly devolved to Holyrood: such as justice, home affairs, rural affairs, the environment etc etc and - you've guessed it - etc.
How can it be, he says, that Holyrood is not to be consulted on such matters which virtually define its list of powers?
Ah, say UK ministers, Holyrood will be "consulted" - but not via the requirement for an LCM. The legislation only covers the EU ambit with regard to such devolved matters. Not the matters themselves. Thus it is foreign affairs and/or the constitution. And so reserved.
Nonsense, says Mr Russell, this is legislation directly affecting devolved matters. LCM required - and, for now, there is no majority at Holyrood for such consent to be granted.
To be clear, again, Mr Russell does not and will not threaten that this situation amounts to a prospective veto - even if his interpretation proves to be correct.
For one thing, his objective is to use the possibility of an LCM as a negotiating lever to give him more clout in Part One - the formulation and promulgation of UK Brexit policy.
For another thing, Mr Russell and Ms Sturgeon are only too well aware of the limits of an LCM. Suppose it is eventually conceded that an LCM there must be. That Holyrood must vote upon the EU departure bill.
Holyrood may then decline to give consent, presumably on the grounds that the other element of the deal - Part One - has not gone well, from the perspective of Scottish Ministers.
But, at the pinch, UK Ministers may then say: "So Holyrood declines to consent? These things. How sad. We had hoped to proceed by consensus but hey and, indeed, ho. Westminster is sovereign. Onwards and upwards."
Not, you will readily understand, particularly good politics. Mrs May and her colleagues will indeed wish to proceed via consensus if possible. But the issue of sovereignty remains there, in the background. If needed.
For now, we await the detail. In particular, we await the triggering of Article 50 in the spring and the introduction of the Bill in the subsequent Queen's Speech. But matters are moving.