Simon Carr: Mr Speaker... author of a great Jekyll and Hyde psychodrama

Can we have a debate on fawning sycophancy, shameful grovelling, unctuous toadying, ritual subservience and the Liberal Democrats?"

That was John Bercow's question from March 2001, in his carnivorey-Tory days when he described the Liberal Democrats as "a left wing party scavenging for right wing votes". He's come a long way since then. Life is a journey. Maybe he'll be saying it again in five years' time from the House of Lords.

There is, coincidentally, some talk at the moment of a Liberal Speaker to replace him. The last one was elected 80 years ago in 1921. Since then there have been six Conservatives, four Labour and the current one who's a bit of both.

The alternation between the parties hasn't been exactly regular, but the one consistent exclusion has been the Liberal party.

When you look back at John Henry Whitley – he works rather well as a contemporary precedent. He was elected as a "Coalition Liberal" at the end of Lloyd George's wartime government and presided over Conservative and Labour governments for the next seven years.

Currently, the party has three good candidates for the job. Ming Campbell, Alan Beith and David Heath. All clever, experienced, capable and decent.

But their election does require a vacancy, so here's a summary of the argument.

First and foremost, the Speaker has to rise above party and administer the business of the Commons in an impartial, even-handed way.

It's perfectly possible. Betty Boothroyd and deputy Speakers, Sylvia Heal and Alan Haselhurst – from their different parties none has favoured this side or that. They are, in an old-fashioned word, thoroughly respectable.

John Bercow's record is different. Actually it's so different I rather hope he stays on. His dislike of certain Tory MPs is played out so publicly in the House it's a serial psychodrama. It's clear to observers that he Jekylls to Labour and Hydes to Tories. There will be more of that to come, as the temperature rises over the summer.

Then there is his manner, his official language. This is a mash-up of 1950s housemaster, music hall Master of Ceremonies, and TV game show host. It may be his impression of how the dignified parts of the constitution should talk. It conceals a mass of resentments, insecurities and alienation quite at odds with the intended effect.

Now, I won't hear a word against Mrs Bercow. She isn't required to be Caesar's wife in this day and age. But coming out on Twitter for Ed Balls in Labour's leadership campaign wasn't wise. Ed Balls was her husband's patron in some committee of research, and his sympathies are also known. But if the Speaker and his wife are for Balls how are the supporters of the Milibands and Andy Burnham supposed to feel?

And finally, the Wright committee votes at the end of the last Parliament. All votes for committee positions were to be by secret ballot – including the election of the Speaker. The one exception was the RE-election of the Speaker. This special arrangement was stitched together by John Bercow and Harriet Harman, to help keep a pro-Labour Speaker in place – something that would be helpful in a tight Parliament.

It was a blatant manipulation of the constitution for party and personal reasons. And it may well work. Members who vote No in tomorrow's public vote will have their names on a list, and MPs don't like that. Let's see what happens.

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