The history of the post of Speaker of the House of Commons is lengthy and also a shade ambiguous. It certainly dates back to 1377, but commentators have suggested that Peter de Montfort, who served as the “parlour” or “prolocutor” for an assembly that met 750 years ago in Oxford, should be considered the first holder of a version of this position. That gathering, in 1258, was dismissed as the “Mad Parliament” by supporters of Henry III because it attempted to undermine the King's authority.

The description is harsh. First, because that Parliament was wise to move against an incompetent, vain and weak leader. As one eminent Victorian scholar observed: “It would have been well for England if all parliaments had been equally sane.” Secondly, it must now be obvious that the genuine Mad Parliament was the one that elected Michael Martin to sit in its chair on October 23, 2000, despite 11 other candidates being available.

The Speaker is in the mire over his attitude to public money, which clearly has a medieval monarch's flavour to it. He has spent more than £20,000 of our collective cash to rebut negative press stories about him. He has used Air Miles secured in his duties to upgrade seven members of his family on flights, in breach of the advice that his committee offers to parliamentarians.

It was claimed on his behalf that when his wife submitted receipts for more than £4,200 of taxi fares, she had been accompanied by an “official” and was buying food for formal meals. In fact, her companion was her housekeeper and close friend, and the Commons itself provides the catering for any such occasions. Mr Martin has been paid £75,000 over six years in Additional Costs Allowance for a home in Glasgow on which there is no mortgage and he makes a further charge for it because it supposedly doubles as his office (another practice that MPs are, via the Speaker, counselled against). Yet, despite all this, he insists that he sticks not just by the rules but also their spirit.

The only person to emerge from this with any credit is Mike Granatt, the media spokesman who resigned as Mr Martin's mouthpiece because he had inadvertently misled reporters over his boss's expenses. Nine Speakers have died violent deaths: one was murdered, another was killed in battle and seven more were beheaded (two on the same day in 1510). This one is surely the first to have ripped to shreds his own reputation and standing.

To be honest, however, the true costs of this speakership are not Air Miles and taxis.

Mr Martin is probably no worse than dozens of other MPs, especially the older sort, who believe that a little creative accountancy with their expenses could usefully supplement their comparatively modest salaries. His conduct is harder to defend because he is paid more than twice as much as a typical humble backbencher, but I am sure that there have been many excellent Speakers who have also played the system. The real scandal is that the House elevated a man who was manifestly unfit for the role and seven years later it will not press him into overdue retirement.

There are essentially three functions for the Speaker in the modern era - managing the daily business of the chamber, taking charge of a plethora of committees and individuals who run the vast Palace of Westminster and serving as the public face for Parliament.

In all of these jobs Mr Martin has been a monumental failure. His decisions in the House itself have prompted not only Tories but also Labour MPs to question his neutrality. His handling of Prime Minister's Questions has frequently been an embarrassment. His feeble chairmanship of the committees for which he is ultimately responsible has created an atmosphere in which some Members treat the House of Commons as if it were a private club and not a public institution whose loyalty should be to the electorate.

The job of representing Parliament to the wider world is profoundly important. Betty Boothroyd, in particular, demonstrated that a capable and charismatic Speaker could work wonders for the image of the House. Most MPs would agree that her successor, sadly, has been a failure.

Mr Martin, it should be acknowledged, still has a few defenders left - but then so does Mohamed Al Fayed. Rather than do something, though, they prefer to simply muddle through in the hope that he will announce an intention to stand down at the next election, or preferably sooner. Few of them express their opinions openly because that is “not done”, besides which they fear that they might hurt their chances of being “called” in Parliament.

So nothing occurs, while the damage caused to the House of Commons by the expenses exposé becomes increasingly corrosive. It is stoking the dangerous sentiments in the public mind that “they are all the same” and “are all in it for themselves”. This is very unfair. Most MPs are dedicated people who provide excellent value for money. The rules do, nevertheless, need a comprehensive overhaul and Mr Martin is plainly not the man to do it. His deputy, Sir Alan Haselhurst, would be better suited to the job.

Parliament should not carry on procrastinating. Under this Speaker, the Commons is slipping from “order, order” to “chaos, chaos” in the opinion of the rest of the country. It took 14 years from the Mad Parliament for the incompetent, vain and weak Henry III to be followed by the infinitely more dynamic Edward I. Fourteen days would be time enough to be free of Speaker Martin.

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