The Article 50 Bill begins two days’ worth of consideration in the Lords today.  Two main issues are set to be debated during them.  The first is the status of EU citizens from abroad in Britain, which we have covered on this site previously.  The second is the proposal for a “meaningful” vote on the outcome of Theresa May’s negotiation.  Since all votes in Parliament are meaningful, in that they express the view of MPs or peers on the matter before them, what do those who propose this meaningfulness actually mean?

The truth becomes clear once one begins to mull the issues – and the way in which our constitution works.  Parliament can vote in any way it pleases.  If it is dissatisfied with whatever emerges from the Governments forthcoming negotiation with the EU, it can say so.  If it wants to send May back to the negotiating table to have another go, it can say so too.  If it feels so strongly about the matter as to pass a vote of no-confidence in the Government, it can do that as well.

In other words, Parliament is sovereign (or, if you prefer, the Queen in Parliament is sovereign).  This is why diehard Remainers are right to argue that the referendum result is advisory.  MPs have every right to ignore it if they wish.  Whether they would be wise to do so, thereby thumbing their noses at the biggest popular mandate in post-war history is another matter entirely: they would not be, as Alistair Burt writes on this site today.  Neither their constituents – nor, in the case of Conservative MPs, their Associations – would take such a decision lightly.

So the peers who will argue for a meaningful vote this week already have the capacity to cast one – and MPs even more so.  What will the Lords mean, then, if they back one?  The purpose is plain.  It is to force a commitment from Theresa May in advance that if Parliament disapproves of the result of her negotiation she will return to begin another one.  And she doubtless would in due course – in the general sense that discussions between any British Government and the EU 27 about our future relationship are bound to roll on into the future post-Brexit.

This is the heart of the matter.  The way that the Article 50 process works is that a country that applies it leaves the EU automatically after two years of doing so – unless “the European Council, in agreement with the Member State concerned, unanimously decides to extend this period”.  There is an important qualification: it is possible to imagine that the European Court may rule that the process can be paused or abandoned altogether.  But this is not where we are now.

Those who demand that May returns to the negotiating table if Parliament doesn’t like what she brings back are therefore demanding an outcome that would doubtless take place in that circumstance in any event.  But it would happen with Britain outside the EU, not inside it – given the narrow window between the likely conclusion of the coming negotiation (early 2019, unless the talks collapse before then) and the date on which we leave the EU altogether (early 2019, if Article 50 is moved next month).  We would no longer be negotiating as an EU member.

So all that calls for this meaningful vote can therefore achieve is to suggest to our interlocutors that Parliament may not back the Prime Minister when push comes to shove – which hardly strengthens her negotiating position.  There is only one other possible intepretation.  It is that those who call for it are somehow hoping that (although the facts suggest otherwise) if peers and MPs niggle and procrastinate and nitpick for long enough, Brexit can somehow be delayed – or abandoned altogether.

We end where we started.  MPs and peers have every right to reject whatever deal the Government agrees – if there is one at all – and then to vote that May return at once to the negotiating table.  But she, for her part, has every right to ignore them if she so chooses.  If Parliament then decided that it has no confidence in the Government, she would be entitled to seek to fight a general election on the matter, arguing that MPs and peers are seeking to defy the referendum result and, in doing so, abandon any prospect of control on EU migration.

In such circumstances, a way would doubtless be found of getting round the Fixed Terms Parliament Act.  I rather fancy the Prime Minister’s chances in such a poll. Don’t you?