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Also: if you’re on London on 8 October, you might be interested in this Guardian Live event. Brexit, how likely is a no-deal exit? Join chair Zoe Williams and our panel of Guardian writers including chief leader writer Randeep Ramesh; Lisa O’Carroll, Brexit correspondent; and Rowena Mason, deputy political editor, as they discuss the unfolding Brexit chaos.

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The last week began with a bombshell when the 11 judges of the supreme court ruled unanimously that Boris Johnson’s decision to prorogue parliament for five weeks at the height of the Brexit crisis was “unlawful, void and of no effect”.

In an clear decision asserting the supremacy of parliament over government, the court said the prime minister’s move “had the effect of frustrating or preventing the ability of parliament to carry out its constitutional functions without reasonable justification”.

Johnson, who was in New York for a UN meeting, said he “disagreed” with the judges’ opinion and suggested he may try to send MPs home once again. He then cut short his stay and flew back to Britain to face the fury of a reconvened parliament.

During a highly acrimonious session in the Commons, the prime minister subsequently caused outrage by dismissing calls to stop using inflammatory terms such as “surrender”, “traitor” and “betrayal” in relation to Brexit, saying the best way to honour the memory of murdered MP Jo Cox was to “get Brexit done”.

Despite thinly-veiled criticism from Church of England bishops, his sister Rachel, Amber Rudd (who said his rhetoric legitimised violence) and many others, Johnson passed up multiple opportunities to apologise, repeatedly refusing to say sorry.

No 10 promised Johnson would not be toning down his language at the Conservative party conference either and his adviser Dominic Cummings insisted the only way threats and abuse would be stopped was if MPs “respect” the result of the EU referendum.

Many MPs are convinced Johnson’s choice of language is a deliberate effort to whip up anger in the country against them in order to motivate pro-Brexit voters to back him; the Speaker, John Bercow, summoned all party leaders to peace talks.

Meanwhile, opposition MPs flexed their muscles again, rejecting the government’s call for a mini-recess for the Conservative conference and discussing plans to force Johnson to request a Brexit extension earlier than the current 19 October deadline.

Amid fears Johnson might try to invoke emergency powers or simply ignore the Benn act obliging him to seek a Brexit extension beyond 31 October, a cross-party group of MPs planned to seize control of parliament to strengthen legislation against a no deal.

On the EU side, Ireland’s Leo Varadkar said the UK must table written proposals on how it plans to replicate the Northern Ireland backstop within the week. Jean-Claude Juncker said responsibility for no deal would rest solely with the UK and Michel Barnier added that Johnson’s antics had “limited the chance” of a deal.

The early stages of the Tory conference in Manchester were dominated by discussion of allegations that Johnson groped a journalist’s inner thigh at a dinner. And despite it all, a new poll showed the Conservatives hold a 12-point lead over Labour.

What next

The formal exit date of 31 October can only be observed if Johnson agrees a new deal with the EU, which is then approved by parliament; the Benn act obliges him to write to the EU seeking a new extension if no deal has been reached by the 19 October.

However, it is highly unlikely a deal could be reached at the EU summit on 17 and 18 October, and any agreement would in any case require the improbable Commons support of ex-Tories stripped of the party whip and some Labour rebels.

The prime minister has said repeatedly he will abide by the law, but also that he will not seek an extension. He has not said how he will square that circle. So what might happen?

There has been speculation he could declare an emergency using the 2004 Civil Contingencies Act or write a “second letter” to the EU revoking the first, both of which would be open to legal challenge.

Alternatively, he could resign in order to pose as a Brexit martyr or – perhaps most likely, but not immediately – be ousted in a vote of no confidence, allowing a caretaker prime minister to ask Brussels for the delay and dissolve parliament.

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In the Guardian, Joris Luyendijk argues that Europe is not the the enemy and demonising the EU is undermining Britain:

It is essential to distinguish between the rightwing papers and politicians that whip up hatred in Britain, and the rest of the country … The EU needs to protect Ireland and make sure that if the UK opts for the no-deal disaster so many of its mainstream leaders and publications crave, it is clear to the rest of the world who is to blame. Because Brexit is something that the UK is doing to its European neighbours, not the other way around. For years now, a decisive segment of the British establishment and electorate has been poisoning itself with lies, delusions and the demonisation of everyone with a different opinion about membership of the EU. These people want to throw themselves off a cliff and take their country with them. It is a deeply painful process to follow, especially for those who know that a different Britain is possible. Alas, the EU cannot save a country that does not want to save itself.

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A fair point, when all’s said and done: