The government's Brexit timetable is set to be knocked off course

In withholding support for Boris Johnson’s Brexit deal until the Withdrawal Agreement Bill (WAB) has passed, MPs have changed the dynamics of the Brexit debate once again. Not only have they forced the government to request an Article 50 extension, but they may have turned the tables on – and could change the shape of – the WAB. This has left the government on the back foot, unable to guarantee leaving on 31 October, and reliant on how others – including the Speaker, Parliament and the EU respond to the latest stalemate.

Having returned triumphant from the EU with a revised Brexit deal, Boris Johnson’s next challenge was clear: convince MPs to approve his deal in a straightforward yes/no vote, with Parliament’s approval removing the obligation in EU (Withdrawal) (No.2) Act (the Benn Act) to request an extension from the EU. With that hurdle passed, the government could have introduced the WAB – which needs to make it onto the statute book before the deal can take effect. The government could have argued that it was this deal or no deal, threatening to pull the bill and proceed with no deal if Parliament tried to derail the bill’s progress, with precious little time or opportunity for parliamentarians to try (again) to prevent no deal.

But the Letwin amendment has changed the ground rules. The meaningful vote didn’t take place – and the Speaker has ruled out another vote before the WAB is introduced on the basis that the substance of the motion and the circumstances in which the House is being asked to consider it are the same. An extension has been requested. And the WAB still needs to be introduced. The government could find its timetable disrupted at any stage, leading to either a short ‘technical’ extension to allow more time to pass the WAB or a longer one if an election or second referendum looked necessary to break the parliamentary deadlock.  

The challenge on Tuesday: tabling Brexit legislation 

The government is expected to present the Withdrawal Agreement Bill to Parliament on Monday and ask MPs to give the bill its second reading on Tuesday. If passed, this could indicate that there is a majority to be found in Parliament in favour of the deal and for implementing legislation.

However, this is a big if: once the WAB is published, MPs will finally be able to see what this bill looks like in practice – and may not be comfortable with its contents. Even if MPs support the bill at second reading, it doesn’t mean they will continue to do so during its later parliamentary stages. Labour MP Lisa Nandy has suggested she would vote for second reading with the aim of allowing the bill to progress to a stage when it can be amended. There is no guarantee that passing the bill at second reading is a reliable proxy for a ‘meaningful vote’ on the deal.

The challenge on Wednesday: tabling a programme motion and facing possible amendments

The government will try and schedule parliamentary time – through a programme motion – so that it can pass the legislation at speed. This will probably be voted on – unamended – immediately after second reading. If MPs vote this down, then the government will almost certainly be unable to guarantee the WAB will pass in time to leave on 31 October. It could ask MPs to agree ‘guillotine’ motions which would limit the time available for each stage of the bill, or try another programme motion again at a later stage. But a programme motion introduced then could be amended – creating further risks for the government.

The government could also face amendments to the WAB which could derail its plans. Even if the programme motion passes, the government could yet be derailed by amendments that could require it to reopen negotiations or risked threatening UK or EU ratification of the deal – such as attempts to require the government to negotiate a customs union or hold a confirmatory referendum. In effect, the committee and report stages of the WAB could act as a new series of indicative votes on different Brexit options. 

MPs are also likely to demand a greater role for Parliament in the future relationship negotiations. Boris Johnson has already indicated that parliamentary select committees could play a role. He has also committed to adopting the Nandy–Snell amendment from March which would require Parliament to approve a negotiating mandate for the future relationship, and sign off any final trade deal with the EU. However, the government may be wary of making concessions it may later regret, given the challenges it has faced in securing approval for the Withdrawal Agreement.

The challenge to be confirmed: getting legislation through the House of Lords

Even if the government can get through the Commons, the WAB must get through the second chamber. The government has less control over time in the Lords, and is less able to rely on the whipping system to force peers to support the government. Difficult amendments made in the Lords could force the government to make concessions, and could make life difficult when the bill returns to the Commons for ping pong.

The full effect of the Letwin amendment is yet to be seen, but it seems the government has lost the upper hand. While Oliver Letwin his said his amendment was solely about the question of how the EU (Withdrawal) (No.2) Act (Benn Act) would take effect, its passing has opened up many more questions – with no obvious answers – for the government. What happens next is reliant on how the Speaker, Parliament and the EU respond.