The decision by Boris Johnson to stand for Mayor of London should be celebrated by all those who mourn the dearth of mavericks in British politics. In an age of identikit politicians, where long years in local councils, the “new” universities or trade unions are considered the only worthwhile path to power, it is refreshing to see someone as original and untrammelled by normality as Mr Johnson throw his multicoloured woolly ski hat into the ring.

Marching in a long tradition of politicians who cannot easily be categorised, let alone whose actions can be in any way predicted, Mr Johnson’s career has always been an accident that never waits long to happen. Yet the British people have forgiven him time and again because he is so wildly unlike the usual ruck of nonentities who crowd both sets of benches at Westminster. Of course whether that means they will allow him to control thousands of jobs, billions of pounds and the 2012 Olympics is another matter.

There are several reasons why there are so many fewer mavericks in politics today than in any period since the Restoration of 1660. It seems paradoxical, but at a time when Britain ruled a quarter of the world’s land surface voters expected fewer formal qualifications from their representatives than today, when Britain’s surface fleet is now barely a coastal defence force. It was considered perfectly normal in 1880, for example, for the wildly eccentric Colonel Fred Burnaby – who vaulted over billiards tables and could carry a pony under each arm – to stand for Parliament for Birmingham. (Five years later he attached himself without permission to an expedition to the Sudan and was speared to death by a dervish.)

John Wilkes, whose sexual escapades eclipse even those of Boris, was adored by the public despite his conviction for obscenity, his drunken heretical routs with the notorious Hellfire Club, his libelling of George III and his support for the rebellious American colonists. Had there been a late 18th-century version of Have I Got News for You, he would have been its wittiest panellist. He believed it only took ten minutes of conversation for him to be able to get any woman to ignore his gross squint and misshapen jaw and to wind up in his sexual thrall. Three times the voters of Middlesex elected him to Parliament, knowing perfectly well that as a formal outlaw he could not take his seat.

Yet it is not only flirtatious, priapic mavericks who are preferred by the British people to those whom the Establishment expect and demand that they elect. The painfully serious atheist Charles Bradlaugh was elected MP for Northampton in 1880, was unseated for refusing to take the Christian oath, was re-elected in 1882, was then excluded from the Commons in 1883, was rereelected in 1884, was excluded again in 1885 and then re-re-re-elected afterwards, when finally he was allowed to take his seat. He stayed on as MP for Northampton for the rest of his life, in an age of Victorian religiosity.

The mavericks often have the last word; after all, the names of Wilkes and Bradlaugh live on in history when any number of their contemporaries who lived blameless, hard-working lives and made it to the Cabinet are forgotten by all but pedantic historians, such as me. In 50 years’ time, when questions arise on Who Wants to be a Billionaire? about the famous Tories of the early 21st century, the name of Boris Johnson is likely to loom larger than half the present Shadow Cabinet.

Because politics was rarely a full-time profession before the Second World War, and people who entered it then tended to have their own hinterland, private incomes or outside interests, MPs cared far less what their colleagues thought of them. The true maverick must at heart be a confirmed egoist, as were many of the “awkward squad” of MPs who brought down Neville Chamberlain in the Norway Debate in May 1940, which made Winston Churchill Prime Minister.

Rebels such as Lady Astor, Harold Nicolson, Admiral Keyes, Leo Amery, Harold Macmillan, John Profumo and Quintin Hogg – heroes all for what they did that night – came under tremendous pressure for their actions from their constituents, but they stayed true to their principles while the vast majority of MPs obeyed the whips. If they had been machine politicians of the kind churned out today, would we have ever had the “blood, tears, toil and sweat” speech given by the 20th century’s arch maverick politician – Churchill – a man who crossed the floor of the Commons not once, but twice?

More modern mavericks have included Gerald Nabarro, Alan Clark, Austin Mitchell, Bob Marshall-Andrews, Cyril Smith, Ken Livingstone and – like him or loathe him – “Gorgeous” George Galloway. It is doubtless a sign of a deep psychological disorder on my part, or more likely evidence of a fundamental lack of seriousness, but I would far rather have dinner with any of them than with any chairman of the most powerful select committees in Westminster. (At a dinner I attended some years ago, Ken Livingstone agreed with the zoo owner John Aspinall that the representatives of animals should have seats in Parliament as well as of humans: how maverick is that?)

In an age that values accuracy over flair, statistics over emotion, calculation over romance, there is less and less room for the maverick. The rough edges are knocked off our legislators earlier in life, and the Whips Office is automatically stronger in a system where people see politics as a lifetime’s career rather than – as in the now distant days of noblesse oblige – a way to serve the community.

Should, as seems likely, London’s choice really lie between Ken Livingstone and Boris Johnson, we ought to celebrate it being the first election for decades when a maverick can’t lose.

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