Can MPs stop Boris Johnson if he's determined to carry out a no-deal Brexit?

Politics Explained: MPs are waking up to the reality that it will be harder to prevent the next prime minister, than when Theresa May made the threat

Theresa May had barely wiped the tears from her eyes before Boris Johnson fired a bazooka that struck fear into the hearts of MPs trying to stop a no-deal Brexit.

Striking the hardest-possible stance, the strong favourite to follow her into No 10 vowed he would crash the UK out of the EU if necessary – and would do so as soon as the end of October.

There would be no more pleading for extensions to Article 50, Mr Johnson insisted, telling his – no doubt top-buck paying – audience in Switzerland: “We will leave the EU on 31 October, deal or no deal.”

The pledge came as MPs wake up to the reality that it will be harder to prevent the next prime minister carrying out a no-deal Brexit than when Ms May made the same threat.

At the start of this year, the mechanism was the requirement for amendable motions each time the Brexit deal was put before MPs – allowing the Commons to legislate against a crash-out.

But what if Mr Johnson (if he wins the Tory race) fails to negotiate new terms with the EU (spoiler: he will), so there is no deal and MPs are shut out of the process? Does a no-deal exit become inevitable?

According to the respected Institute for Government (IfG), the answer – legally – is yes, because “parliamentary procedure offers no route”.

“It looks like a near impossible task for MPs to stop a prime minister who is determined to leave the EU without a deal,” the IfG argues.

But, before you start stockpiling spam and essential medicines, there are a couple of possible escape routes.

First, John Bercow’s record suggests the Commons speaker will help MPs create new amendable motions in order to pass a fresh law against a no-deal Brexit, perhaps by staging emergency debates.

Second, there is the nuclear option – already floated by some pro-EU Tories – of toppling their own government by supporting a no-confidence vote, leading to a general election.

The new prime minister will find a working majority of just six, even if the Democratic Unionist Party stays on board – meaning just four Tories would need to switch sides for that vote to succeed.

So, even if Mr Johnson isn’t bluffing – and, remember, the last woman was – it is not necessarily our fate to end up with what is commonly agreed to be the disaster of a no-deal Brexit.

And that election, if that’s how it ends up? The most likely outcome would be Jeremy Corbyn having to turn to the SNP to form a government – whose price would be a Final Say referendum on leaving the EU or staying in.