Can I now turn to Sewel and as far as the Sewel convention is concerned, I think that I have already foreshadowed that the importance of the Sewel convention is not, in our submission, its legal enforceability, but that it represents a dialogue between Parliament and the devolved legislatures.
Now, that dialogue is important for at least two reasons. The first reason is that it is a dialogue between legislatures, and I don't need to emphasise, but I think I ought to, to this court, that the degree of autonomy or sovereignty of a devolved legislature is a sensitive area and it is a growing area for some of the devolved legislatures. There has been case law in the Supreme Court, and perhaps notably, the Axa case.
There is undoubtedly an emerging sovereignty. It is not the same, we know, as Westminster sovereignty, but it is a growing sovereignty of the devolved legislatures, and it is an important area.
The second point is that the Sewel convention in its structure envisages -- it doesn't matter what the word ordinarily or normally means at the moment for this purpose -- a legislative dialogue between two legislatures of different competences, but nonetheless of legislative competence. It, therefore, third point, requires the Westminster Parliament to consider whether it is going to legislate without the consent of the devolved legislature in question.
Now, the fourth point therefore is this. The evaluative decision as to whether to legislate or not is Westminster. But it is not the prerogative. So if the prerogative can be used to short-circuit this dialogue, it is in our submission to ignore the development, the devolution development, the modern dynamic devolution development on which our constitution is materially predicated now that we have devolution in very strong form.
This, of course, is not an argument on legislative interpretation, nor is it an argument on the legal enforceability of the Sewel convention. It is an argument on the common law approach to the prerogative.
Nor, indeed, as I think I said earlier, does Sewel necessarily stand in isolation when one is building up a common law anatomisation of the Sewel convention. For example, Ms Mountfield, I know, has a historical analysis, and it is going to be directed to the fact that in context, the use of the prerogative has never been used in this kind of way. That is a separate argument, and not one that I intrude on.
But when you look at all the sources of information, the common law attaches to itself to analyse the legal scope of a prerogative power, Sewel is very important in that approach, as is history, as to some extent are the commentators.
If I can take your Lordships very briefly, if I can find it in my own authorities, it is the Agricultural Sector (Wales) Bill case, 2014, it is in the authorities at volume 20. And I wanted to -- it is tab 246, electronic page 6837.