Servant of the House: How Speaker's role has evolved
The Commons Speaker, John Bercow, is not afraid to stick his neck out - but at least he won't get his head cut off, unlike a few of his predecessors....
It has always been a role with the potential for controversy.
Sir Peter de la Mare, the Speaker or "Prolocutor" of the Good Parliament in April 1376 opened the first day with a long address on the shortcomings of the Crown - military failures, financial and moral corruption. Royal favourites were imprisoned. King Edward III's mistress, Alice Perrers, was condemned to "seclusion".
But by the autumn, royalty had fought back. The Parliament was dissolved and most of its work was undone. The King's mistress was back at Court.
The King's son, John of Gaunt, had Sir Peter de la Mare thrown in jail.
And the new Speaker was John of Gaunt's own steward, the far more biddable Sir Thomas Huntingford.
Until the 17th Century, the Speaker's loyalty was to the Crown rather than to MPs. But they were often blamed if they delivered news the monarch didn't like.
It could be a dangerous job: seven Speakers were beheaded between 1394 and 1535. That's why even today a new Speaker traditionally makes a show of being dragged reluctantly to the Chair.
Staying on the right side of the Crown was especially tricky during the turmoil of the Wars of the Roses, when it was hard to be sure who would end up being the King. One Speaker, John Wenlock, tried to hedge his bets by fighting on the side of both the Yorkists and the Lancastrians.
It didn't work out well. He was killed at the Battle of Tewkesbury, allegedly by his own commander who blamed Wenlock's general indecisiveness for the defeat.
Gradually, the Speaker's role became one of representing Parliament, rather than the monarch.
When Charles I came in person to the Commons on 4 January 1642 to arrest five MPs for treason, Speaker William Lenthall refused to reveal where they were. Hitherto seen as a rather timorous chap, this was his moment.
He fell to his knees, but told the King: "May it please your Majesty, I have neither eyes to see nor tongue to speak in this place but as the House is pleased to direct me, whose servant I am here."
The King was humiliated and left without the men he'd come for.
John Bercow is being criticised by some MPs today for - in their view - failing to be impartial on political issues. But the Speaker's impartiality is a relatively modern notion. In fact, some Speakers held other government offices at the same time.
They could take part in some debates and vote, when they weren't actually presiding over business.
Arthur Onslow, who had the job for more than 30 years, began to change that. In fact, he used to boast of his impartiality - to the great irritation and disappointment of the Prime Minister, Sir Robert Walpole, who'd helped him to the job.
It wasn't until the Victorian era that our current ideas of impartiality became the norm - though Irish Nationalists in the 1880s felt that Speaker Henry Brand stepped over the line in helping to put down their disruption in the Commons over Irish Home rule. In January 1881, they prolonged debate for 41 hours.
There were disorderly scenes. Irish MPs defied the Chair. And so, Speaker Brand helped the government to invent new procedures, still in use today, to cut the debate short on the Coercion Bill for Ireland.
In spite of the controversies, it's almost unprecedented to sack a Speaker.
Although in recent times, Michael Martin, was pressured into resigning, the only other one to be ousted forcibly was Sir John Trevor in 1695, who'd been found guilty of accepting a £1,000 bribe.
He also had the disadvantage of being so cross-eyed that MPs couldn't tell if he was giving them the nod to speak, or looking at someone else.
And of course, for any MP who tries to oust a Speaker but fails, there's a big risk that in future debates, the Speaker seems strangely unable to see them at all, when they're hoping to be called.