Michael Martin arrived in his Commons office yesterday dogged in his determination not to become the first Speaker to be involuntarily ejected from office in more than 300 years.

Despite a torrid week in which anger over MPs’ expenses was coalescing around his Speakership, the whips were not yet of the view that Mr Martin’s career was finished.

No matter that Nick Clegg, the Liberal Democrat leader, had called him “far too weak on issues such as expenses and freedom of information” the previous morning — making him the first party leader in modern history to call for the Speaker to quit.

Nor did they regard as fatal the challenge from 15 MPs who had signed a motion drawn up by Douglas Carswell, a long-term Martin opponent, saying that the Commons “has no confidence in Mr Speaker and calls for him to step down”.

Since the Government controls business on the floor of the House, they believed, there was little danger that the motion would be debated. Instead the order went out to Labour MPs to tough it out. Mr Martin’s opponents were, whips claimed, to be dismissed as the mutterings of a few bitter backbenchers aided by an opportunistic Liberal Democrat plot.

Unusually for Mr Martin, he was in London for most of the weekend, spending Sunday morning at Mass before seeing Gordon Brown in the evening.

Friends said that MPs could expect a new penitent tone — albeit from a Speaker with no intention of standing down. “He is a proud man. He does not want to be forced out. He has always been resolute all the way through and there is no indication that this has changed,” said a Labour MP close to Mr Martin.

After a weekend on the phones, Mr Brown’s Praetorium Guard — led by the veteran Scottish whip Tommy MacAvoy — felt that contrition might well be enough. With the recess starting on Thursday and no significant business due to be discussed in the Chamber, many MPs would disappear to their constituencies for a 12-day break.

Downing Street also judged that MPs collectively did not have the nerve to force out Mr Martin in a public confrontation. All they needed to do was get through 36 hours without a public revolt. They failed.

When Mr Martin stood up at 3.30pm and addressed a hushed House, the tone had indeed changed and the apology badly missing from a similar statement the week before was now forthcoming.

“Please allow me to say to the men and women of the United Kingdom that we have let you down very badly indeed. We must all accept the blame and, to the extent that I have contributed to the situation, I am profoundly sorry.” Mr Martin, so long the embodiment of stubbornness, appeared to have understood the public anger.

“Now each and every member, including myself, must work hard to regain your trust.” But he said not a word about his own future.

There is more than a suspicion that Mr Brown had expected a nod to his departure before the next election. The Prime Minister left a split second after Mr Martin finished reading — a gesture that told its own story. It was only when he had finished that the events described by one senior Tory as a “train crash” began to unfold, and they were unprecedented scenes that appeared to have sealed the fate of Mr Martin.

Speakers are never criticised to their face in the Commons, any more than her royal subjects would tell the Queen to abdicate to her face. But MPs from all parties stood up to complain, starting with Gordon Prentice, a Labour backbencher on the Public Administration Committee, who called for a debate on the Speaker’s resignation. MPs began to heckle when Mr Martin tried to claim that the subject of his future could not be debated on a technicality.

He appeared on the brink of losing control as Sir Patrick Cormack, a veteran Conservative, summed up the mood. “May I ask you to bear in mind that the condition of the House today is rather like the condition of the country at the time of the Norway debate [before the resignation of Neville Chamberlain], and could you reflect on that?” Mr Martin did not reply.

In the moments that followed, many MPs were in shock at scenes of rebellion against the Speaker not known in living memory. The consensus afterwards of MPs was that the performance had been a disaster and that Mr Martin had sealed his own fate. But last night Mr Martin still seemed in denial, and the manner and timing of his departure were as much a mystery at the end of the day as at the beginning.

QUESTIONS & ANSWERS

Michael Martin did not resign, so why was yesterday important?

The authority of the Speaker of the Commons rests on the respect of MPs. Yesterday it became clear that he had lost the esteem of significant numbers of Members. He appeared to strain to keep control of the chamber at one point.

If this was a public execution, why did it all look so polite?

In parliamentary terms this was a bloodbath. But conventions require MPs to act with decorum. That MPs were questioning his authority to his face is virtually unprecedented.

Why did Mr Martin not step down?

It is constitutionally almost impossible to sack a Speaker. Party leaders cannot be seen to do so, since Parliament ought to be separate from the Government and governments-in-waiting. MPs are unwilling to go public with their views in case of retribution, and Mr Martin is stubborn. He refuses to recognise that his reluctance to stand down is damaging Parliament, the Labour Party and Gordon Brown.

Why can’t MPs debate his future?

Decisions about what MPs can discuss are made by the Government, which is refusing at the moment to grant time to debate the subject. MPs can put motions calling for the Speaker to resign on the order paper, but they will just stay there, undebated.

What did the Speaker mean when he said that Douglas Carswell’s motion was an EDM?

Mr Martin suggested — wrongly — that Mr Carswell’s motion calling for his resignation was a symbolic parliamentary gesture known as an Early Day Motion, which never gets discussed and is used to show support for an issue. Actually, it has been accepted by parliamentary clerks as a full motion that could be discussed by MPs in the chamber.

So will it be debated?

This remains a decision for the Government and Harriet Harman as Leader of the Commons. Neither the Government nor the Conservatives are likely to move on the issue unless many more MPs sign up. Last night the motion had attracted 18 signatures.

Why else were MPs upset?

In a completely unexpected move, Mr Martin asked them to stop submitting expense claims until the system was sorted out by Sir Christopher Kelly, the chairman of the Committee on Standards in Public Life. This could be November. Many MPs fear that being deprived of their significant allowances to pay second mortgages will result in their colleagues being bankrupted.

What happens next?

Neither the Labour nor Tory leadership wants to be seen crossing the line and forcing him out. They hope that one of two things will happen: that Mr Martin steps down of his own volition — which he is showing no inclination to do — or that MPs sign Mr Carswell’s motion in such great numbers that the Government has to agree to its being debated. But the moment that happens will be the moment that Mr Martin sees the writing on the wall — and walks.

Order of succession

The selection of the next Speaker will be the first conducted by secret ballot. The favourites are:

Sir George Young (4-1) Tory chairman of the Standards and Privileges Committee. Seen as the favourite, but he is an Old Etonian, which may deter Labour and some Tory supporters

Sir Alan Haselhurst (5-1), Tory Deputy Speaker. Chairs Budget debates. Well liked but wounded over recent expenses allegation. Would be seen as a temporary fix

Vince Cable (no odds) Lib Dem Treasury spokesman. Doesn’t want the job — which may make him ideal. Lib Dems would get their own man. Tories would see off their most feared political enemy. Labour would be pleased because he used to support them

John Bercow (no odds) Tory backbencher. Having crossed the ideological desert Bercow is now a moderniser. Labour figures will find him more palatable than Tories

Sir Menzies Campbell (5-1) Former Lib Dem leader. Despite being tipped, his chances are not high after a disastrous Question Time appearance when he defended questionable expense claims. He would not be a reformer and too close to the Establishment

Frank Field (9-1) Maverick Labour backbencher. Former minister is seen as a radical moderniser by opponents, but as an opportunist by his own side

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