On Tuesday MPs made the significant move of backing a plan to give the Commons more power to dictate what happens if the prime minister’s approach is ditched.
The twin developments deliver both a means for MPs to secure a new referendum and legal clarity that they could halt the Brexit process if the public then decided to remain in the EU.
The government’s weakness was once again underlined as it lost three consecutive votes – including one unprecedented defeat which resulted in Ms May’s administration being held in “contempt of parliament” for refusing to publish legal advice on the proposed Brexit deal.
At the start of the week campaigners delivered petitions carrying almost 1.5 million names to Downing Street, which demanded the British public have a Final Say on Brexit through a people’s vote.
While Ms May remains adamant there will be no new referendum, MPs are already looking ahead to how parliament can impose its will if her deal is rejected in the commons vote on 11 December – something which now seems inevitable.
Conservative, Labour and Liberal Democrat MPs tabled and won a vote on a motion significantly increasing the ability of parliament to steer the path of government if Ms May’s plan is defeated.
Leader of the Commons Andrea Leadsom had urged MPs to “focus on the matter at hand” rather than what would happen if Ms May’s deal falls, but in the end the motion was passed by 321 votes to 299.
Former attorney general Dominic Grieve, who had led the drive, told MPs: “The reality remains that we have an unsatisfactory procedure to resolve differences of opinion in this house, if and obviously it’s an if, we come to a point where the government does not succeed on its motion.
“The opportunity exists this afternoon to cure that anomaly.”
Under the process already laid down, the government must within 21 days make a statement on how it will proceed if it loses the 11 December “meaningful vote” on Theresa May’s Brexit deal.
Currently parliament would effectively only get to consider that plan, but after last night’s motion was passed it can now table and vote on amendments to it.
It means they will most likely look to pass an amendment preventing a no-deal Brexit, for which there appears to be a majority in the house, or to potentially pivot to taking the country into a Norway-style arrangement or to holding a new referendum.
Brexiteers immediately pointed out that any amendment passed under the motion would not have legal force to tie the government to any course of action.
Steve Baker, who organises Tory Eurosceptic efforts in the Commons, said: “Grieve’s amendment ... allows for an amendable motion 21 days after a government defeat of their dreadful deal.
“Whatever the outcome of the amendment, it is not legally binding on the PM. Acts are law, motions are motions. The executive still decides how to proceed.”
But a motion passed after the defeat of Ms May’s plan, with the backing of the majority of the Commons for a particular course of action, would carry considerable political weight and be very difficult for the government to ignore.
A report released by the People’s Vote campaign on Tuesday also set out other ways in which MPs could seek to steer government action, by amending other legislation still required for Brexit, for example.
On Tuesday morning the European Court of Justice’s advocate general formally advised that Britain could still cancel Brexit by revoking Article 50.
The legal recommendation cited Britain’s “sovereignty” in treaty-making matters and said withdrawal “may be revoked at any time” during the negotiating period.
Chris Bryant MP, champion of the People’s Vote campaign, said: “The terms of the Brexit debate have today fundamentally shifted.
“The government has long argued that the choice is between their deal and no deal. But the statement this morning from the EU advocate general shows the option of staying in the EU is still open to us.”
Ms May’s administration lost two other votes earlier in the day at the hands of shadow Brexit secretary Sir Keir Starmer, with the government found in contempt of parliament and being forced to release legal advice that it had wanted to keep confidential.
Kicking off five days of debate on her Brexit plans, the prime minister then said her deal was the “only solution that will endure” and “bring the country together”.
To those arguing for a looser arrangement, she said any deal had to respect the concerns of the 48 per cent who voted to remain, so as to “protect the trade and security cooperation on which so many jobs and lives depend”.
She also said: “I know there are some in this house and in the country who would prefer a closer relationship with the European Union than the one I’m proposing, indeed who would prefer the relationship that we currently have and want another referendum.
“Although I profoundly disagree, they are arguing for what they believe is right for our country and I respect that, but the hard truth is that we will not settle this issue and bring our country together that way and I ask them to think what it would say to the 52 per cent who came out to vote Leave in many cases for the first time in decades if their decision were ignored.”
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