The European Union (Notification of Withdrawal) Bill, to quote a well-known advertisement, does exactly what it says on the tin. In response to the Supreme Court’s judgment that an Act of Parliament is needed to trigger Brexit, the Bill provides that Theresa May ‘may’ give notice under Article 50, perhaps an interesting choice of words given that the Bill does not specify a time-frame for invoking Article 50.

David Davis, Secretary of State for Exiting the Union, in charge of the Bill, rather testily said it was ‘to deliver the instruction from the nation at large… a straightforward, easily comprehensible Bill so that the country at large can see what Parliament is doing and what decision it is visiting on the government’.

Justifying the fast tracking of the legislation because of the need for the Government “to complete an additional (and unexpected) step” [of approval] by the Prime Minister’s self- imposed deadline of March 2017, the Bill is down for Second Reading over two days from Tuesday 31st January – where the principle will be debated – a Committee stage from Monday 6th to Wednesday 8th, February, with the Final Commons stages scheduled for Wednesday 8th, before Parliament rises on 9th for February Half term. There are no dates yet planned in the Lords – the House returns from recess on the 20th.

As promised, Labour have tabled numerous amendments requiring Parliamentary approval of the ‘exit agreement’, an obligation on the government to report progress of the exit negotiations on a two monthly basis, and for Parliamentary scrutiny of confidential documents. The SNP has tabled (as one of 50 such amendments) an amendment preventing Article 50 from being triggered until the devolved administrations have agreed with the government a UK-wide approach to withdrawing from the EU.

One aspect of the Supreme Court’s judgment which has received comparatively little attention is the devolution question, and the role of the devolved administrations in the Brexit process. The Supreme Court came to the view that the ‘Sewel convention’ (which provides that Westminster will not normally legislate on devolved matters) has no legal effect and cannot be reviewed by the courts. This is the case despite the convention being put on a statutory footing by the Scotland Act 2016. It will surprise many (including perhaps the Scottish government) that a piece of legislation can have no legal effect. After all, what could possibly be more legally enforceable than an Act of Parliament? Without the threat of a veto over Brexit, it will be revealing to see how the Scottish government in particular seeks to deploy the political tools still available to shape the Brexit process. The recently-announced Select Committee inquiry into Brexit and devolution may shape how the UK government takes account of the wishes of the devolved administrations and the constitutional settlement of the UK after Brexit.

So, could all this mean that the triggering of Article 50 is prevented? With the main opposition party subject to a three line whip to support the Bill it will interesting to see what, if any, genuine pressure can be brought either in the Commons or the Lords to delay or modify the Bill.