Could Theresa May’s replacement force through a no-deal Brexit?

So Theresa May has reached the end of the road as prime minister. A number of candidates who have thrown their hat in the ring have made it clear that they would rather leave the EU without a deal than the one negotiated by May.

Brexit votes earlier this year have shown that there is a majority in the Commons opposed to a no-deal Brexit – but the procedural options open to them to avoid this outcome are severely limited (unless the Speaker, John Bercow, decides on a more flexible interpretation of parliamentary convention, which is possible).

MPs were most successful in taking action to avoid no deal when they managed to take control of parliamentary time to pass a bill (the “Cooper bill”) which required the government to ask for an extension to article 50 ahead of 12 April (although May had already planned to do so). However, this opportunity came through provisions inserted into the EU Withdrawal Act, which meant that May had to hold a “meaningful vote” on her deal before she could ratify it, and then hold a subsequent vote on the government’s next steps once her deal was rejected.

A new prime minister who wants to leave without a deal is not required to hold this vote; the provisions of the EU Withdrawal Act no longer apply. They can instead limit any opportunities for MPs to express opposition to no deal, and watch the clock count down to 31 October.

So what could MPs do, faced with this situation? The opposition and backbench business committee both get a certain number of days each parliamentary session in which they can decide what motion will be debated. But the government controls when these happen (they didn’t schedule any between November and April while Brexit was the main focus of parliamentary attention) so a new prime minister could just not give them the time to pass any motions.

Unlike opposition or backbench business days, emergency debates under standing order 24 are in the gift of the Speaker, not the government. But by convention these motions are neutral – saying that the House has “considered” an issue – which means they are not amendable. The Speaker did suggest in March that he may be willing to be more flexible in interpreting this convention. But motions are not legally binding – so this would need to be followed up with MPs introducing legislation to direct the government. Not impossible. But not straightforward either.

MPs may also look to table amendments to the new prime minister’s Queen’s speech, which sets out the government’s programme for a new parliamentary session (which takes place after parliament is prorogued and a new session begins). But there is no obligation on a new leader to prorogue parliament – if they were concerned that MPs were going to try to stop no deal they could choose to continue the current session, padding it out in much the same way May has done for the last month.

The Commons could decide to refuse to support the government in any business it brings before the house. But if there isn’t a new session, and no significant legislation, this wouldn’t necessarily cause much concern to a new prime minister.

The other – more obvious – way in which MPs could express opposition to a prime minister intent on no deal would be to hold a no-confidence vote in the government. Provided that there is enough support from Conservative MPs for opposition parties to win such a vote, this would trigger a 14-day period in which someone else could try to form a government which has the support of the Commons. This could be the leader of the opposition, or someone else with the backing of enough MPs. If not, there would be a general election which would need to take place before 31 October to ensure that another prime minister could agree an extension and avoid no deal. So MPs would need to call a no-confidence vote with enough time to allow for the eventuality of a general election before the end of October if they wished to use this route to try to block no deal.

While there is no easy parliamentary route to prevent no deal, the importance of political pressure inside and outside parliament should not be overlooked. Taking the UK out of the EU without a deal, against the wishes of a majority of MPs in parliament, would make it very difficult for a new PM to govern in the weeks and months afterwards.

• Maddy Thimont Jack is a senior researcher at the Institute for Government working on Brexit