9 June 2016

A story originally broken by the BBC this week has gained a lot of column inches, specifically the idea that Parliament’s pro-Remain MPs could work to keep the UK inside the single market even following a vote to leave the EU in the referendum. This has raised the question of how involved Parliament will be in the process to leave the EU. You can see our previous explainer on the nature of Article 50 but this is more about domestic than EU rules.

Legally what involvement does Parliament have in the process for leaving the EU?

As far as we can see, legally, there is no requirement for the UK government to get consent or approval from Parliament before triggering Article 50 (more on the political issues below). The referendum itself is also not directly binding so ultimately when this is triggered will be up to the Government of the day.

MPs could seek to introduce a Private Members Bill to try and restrict the triggering of Article 50 or lay down details of what should be included in negotiations with the EU. However, this is a very long and drawn out process and could take many years, even tabling such a bill is challenging. Potentially more likely, MPs could pass a motion to similar effect and while this would be non-binding, it would apply significant political pressure and be hard to ignore.

Politically Parliament may have a more significant role

So while there is no legal requirement to have Parliament involved before the negotiations begin, politically there may well be a desire to have it involved. This could lead to the Government seeking a negotiating mandate from Parliament before beginning in earnest or setting up committees to explore all the options available and come back with a recommendation. Of course, these could delay the process.

It is also worth keeping in mind that, from a negotiating perspective, the UK Government is unlikely to want to declare its position fully and openly before entering the negotiations. This would put it at a disadvantage given the EU would know where its red lines were and were not. This is often why international trade negotiations are conducted behind closed doors with texts of the agreements released after some delays. It was also reportedly the case during the UK’s recent EU renegotiation.

Parliament will have to approve whatever the final agreement is between the UK and the EU – thanks to the part on international treaties in the ‘Constitutional Reform and Governance Act 2010’. However, there is no requirement for a vote or debate on the issue (it is a form of negative assent, it is approved unless there is a resolution opposing it in either House) and Parliament cannot amend the deal. Furthermore, it is likely to amount to a take it or leave it deal, if it is rejected by Parliament it’s not certain that the EU would be willing to negotiate further or that there would be time to negotiate further under any transition agreement. Of course, Parliament has to at some point repeal the 1972 European Communities Act and replace it with whatever the new agreement is.

Overall, for all the bluster, it’s not obvious that Parliament could legally constrain the Government’s approach to negotiations over leaving the EU. Politically though there may well be desire to keep both Houses involved to ensure the process is transparent and goes smoothly.