The Speaker of the House of Commons is the presiding officer of the House of Commons, the United Kingdom's lower chamber of Parliament. The office is currently held by John Bercow, who was initially elected on 22 June 2009, following the resignation of Michael Martin. He was returned as an MP in the 2010 general election and was re-elected as Speaker when the House sat at the start of the new parliament on 18 May 2010. He was again returned as an MP in the 2015 general election and was re-elected, unopposed, as Speaker when the House sat at the start of the new parliaments on 18 May 2015  and 13 June 2017. 
The Speaker presides over the House's debates, determining which members may speak.
The office of Speaker is almost as old as Parliament itself.
On 6 October 1399, Sir John Cheyne of Beckford (Gloucester) was elected speaker. The powerful Archbishop of Canterbury, Thomas Arundel, is said to have voiced his fears of Cheyne's reputation as a critic of the Church. Eight days later, Cheyne resigned on grounds of ill-health, although he remained in favour with the king and active in public life for a further 14 years.
Although the officer was elected by the Commons at the start of each Parliament, with at least one contested election known, in 1420 (Roger Hunt prevailing by a majority of just four votes), in practice the Crown was usually able to get whom it wanted, indicating that the famous 'defence of the Commons' privilege' should not be seen in isolation as the principal thread in the office's evolution. Whilst the idea of giving this spokesman personal immunity from recrimination as only being the voice of the whole body was quickly adopted and did enhance the Commons' role, the Crown found it useful to have one person with the authority to select and lead the lower house's business and responses to the Crown's agenda, much more often than not in the way the Crown wanted. Thus, Whig ideas of the Commons growing in authority as against royal power are somewhat simplistic – the Crown used the Commons as and when it found it advantageous to do so, and the speakership was part of the process of making the Commons a more cohesive, defined and effective instrument of the king's government.
Throughout the medieval and early modern period, every speaker was an MP for a county, reflecting the implicit situation that such shire representatives were of greater standing in the house than the more numerous burgess MPs.
Until the 17th century, members of the House of Commons often continued to view their Speaker (correctly) as an agent of the Crown. As Parliament evolved, however, the Speaker's position grew into one that involved more duties to the House than to the Crown; such was definitely the case by the time of the English Civil War. This change is sometimes said to be reflected by an incident in 1642, when King Charles I entered the House in order to search for and arrest five members for high treason. When the King asked him if he knew of the location of these members, the Speaker, William Lenthall, famously replied: "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 development of Cabinet government under King William III in the late 17th century caused further change in the nature of the Speakership. Speakers were generally associated with the ministry, and often held other government offices. For example, Robert Harley served simultaneously as Speaker and as a Secretary of State between 1704 and 1705. The Speaker between 1728 and 1761, Arthur Onslow, reduced ties with the government, though the office did remain to a large degree political. The Speakership evolved into its modern form—in which the holder is an impartial and apolitical officer who does not belong to any party—only during the middle of the 19th century.
Over 150 individuals have served as Speaker of the House of Commons.
By convention, Speakers have traditionally been addressed in Parliament as "Mr Speaker", and their deputies as "Mr Deputy Speaker", regardless of their gender or their usual title. Betty Boothroyd was, at her request, addressed as "Madam Speaker". When Betty Harvie Anderson served in the 1970s as a Deputy Speaker, on the other hand, she was addressed as "Mr Deputy Speaker". Eleanor Laing, a Deputy Speaker since 2013, is addressed as "Madam Deputy Speaker".
MPs elect the Speaker from amongst their own ranks.
The procedure for electing a Speaker has changed in recent years.
Until 2001, the election of a Speaker was conducted as a routine matter of House of Commons business, as it used motions and amendments to elect. A member would move"That Mr(s) [X] do take the Chair of this House as Speaker", and following debate (which may have included an amendment to replace the name of the member on whom the Speakership was to be conferred), a routine division of the House would resolve in favour of one candidate. There was, however, a considerable amount of behind-the-scenes lobbying before suitable candidates were agreed upon, and so it was very rare for a new Speaker to be opposed. However, this system broke down in 2000 when 12 rival candidates declared for the job and the debate occupied an entire Parliamentary day.  The House of Commons Procedure Committee then re-examined the means of electing a Speaker and recommended a new system that came into effect in 2007 and was first used in June 2009, following the resignation of Michael Martin.
Under the new system, candidates must be nominated by at least twelve members, of whom at least three must be of a different party from the candidate.
If only one candidate is nominated, then no ballot is held, and the House proceeds directly to the motion to appoint the candidate to the Speakership.
Upon the passage of the motion, the Speaker-elect is expected to show reluctance at being chosen; he or she is customarily "dragged unwillingly" by MPs to the Speaker's bench.
The Speaker-elect must receive approbation by the Sovereign, before he or she may take office.
Though the election of a Speaker is normally non-partisan, there have been several controversial elections in history.
The 1951 election was similarly controversial. After the incumbent Speaker, Douglas Clifton Brown, retired at the 1951 general election, there was a great demand from the Labour Party for Major James Milner to become the first Labour Speaker after he had served as Deputy Speaker for eight years. However, the Conservatives (who had just regained power) nominated William Shepherd Morrison against him. The vote again went down party lines, and Morrison was elected. Milner received a peerage as compensation.
In 1971, having had early warning that Horace King would be retiring, the Conservatives took the lead in offering to the Labour Party either Selwyn Lloyd or John Boyd-Carpenter as potential Speakers. The Labour Party chose Selwyn Lloyd, partly because he was perceived as a weak figure. However, when the House of Commons debated the new Speaker, Conservative MP Robin Maxwell-Hyslop and Labour MP Willie Hamilton nominated Geoffrey de Freitas, a senior and respected backbench Labour MP. De Freitas was taken aback by the sudden nomination and urged the House not to support him (a genuine feeling, unlike the feigned reluctance which all Speakers traditionally show). Lloyd was elected, but there was a feeling among all parties that the system of election needed to be overhauled. Now, a candidate's consent is required before he or she can be nominated.
The last three instances of the election of a new Speaker (1992, 2000 and 2009) have all been relatively controversial.
Betty Boothroyd announced her retirement shortly before the summer recess in 2000, which left a long time for would-be Speakers to declare their candidature but little opportunity for Members of Parliament to negotiate and decide on who should be chosen.
By convention the Speaker severs all ties with his or her political party, as it is considered essential that the Speaker be seen as an impartial presiding officer.
In the House, the Speaker does not vote on any motion, except in order to resolve ties.
If the current Speaker decides to contest a general election, he/she does not stand under a party label, but is entitled to describe himself/herself on the ballot as "The Speaker seeking re-election", under the Political Parties, Elections and Referendums Act. In the past, the Speaker could sometimes be returned unopposed; this has not happened in the last few decades, but they have sometimes faced opposition only from fringe candidates.
When Speaker Edward FitzRoy, previously a Conservative MP, was opposed by a Labour Party candidate at the 1935 general election, there was strong disapproval from other parties and a sub-committee of the Cabinet considered whether a special constituency should be created for the Speaker to remove the obligation to take part in electoral contests. The sub-committee came to the conclusion that Parliamentary opinion would not favour this suggestion; however, in December 1938, with a general election expected within a year or so, a motion from the Prime Minister was put down to nominate a Select Committee to examine the suggestion. The committee, chaired by former Prime Minister David Lloyd George, reported in April 1939 that no change should be made; it found that preventing opposition to a sitting Speaker would be "a serious infringement of democratic principles" and that "to alter the status of the Speaker so that he ceased to be returned to the House of Commons by the same electoral methods as other members or as a representative of a Parliamentary constituency would be equally repugnant to the custom and tradition of the House".  With the outbreak of the Second World War, no general election was held until 1945.
More generally, the convention that major parties do not stand against the Speaker is not as firmly established as is sometimes suggested.
The Speaker's primary function is to preside over the House of Commons.
Whilst presiding, the Speaker sits in a chair at the front of the House.
During debate, the Speaker is responsible for maintaining discipline and order.
In addition to maintaining discipline, the Speaker must ensure that debate proceeds smoothly.
Before the House votes on any issue, the Speaker "puts the question"; that is, he or she orally states the motion on which the members are to vote.
The Speaker does not vote in the division, except when the Ayes and Noes are tied, in which case he or she must use the casting vote. In exercising the casting vote, the Speaker may theoretically vote as he or she pleases, but, in practice, always votes in accordance with certain unwritten conventions, such as Speaker Denison's rule. First, the Speaker votes to give the House further opportunity to debate a bill or motion before reaching a final decision. (For example, the Speaker would be obliged to vote against a closure motion.) Secondly, any final decision should be approved by the majority. (Thus, for instance, the Speaker would vote against the final passage of a bill.) Finally, the Speaker should vote to leave a bill or motion in its existing form; in other words, the Speaker would vote against an amendment.
Since the House of Commons is a very large body, Speakers are rarely called upon to use the casting vote.
In addition to his or her role as presiding officer, the Speaker performs several other functions on the behalf of the House of Commons.
The Speaker performs various procedural functions.
The Speaker is also responsible for overseeing the administration of the House.
Finally, the Speaker continues to represent his or her constituency in Parliament.
The Speaker is assisted by three deputies, all of whom are elected by the House.
Deputies have the same powers as the Speaker when presiding.
Precedence, salary, residence and privileges
The Speaker is one of the highest-ranking officials in the United Kingdom.
In 2010, the Speaker received a salary of £145,492,  equal to that of a Cabinet Minister.
Customarily, Speakers are appointed to the Privy Council upon election. Thus, the present and former Speakers are entitled to the style "The Right Honourable". On retirement, Speakers were traditionally elevated to the House of Lords as viscounts. The last Speaker to receive a viscountcy was George Thomas, who became Viscount Tonypandy on his retirement in 1983. Since that year, it has instead been normal to grant only life baronies to retiring Speakers.
The post of chaplain to the Speaker has historically been held by a Canon Residentiary of Westminster Abbey; in recent years, the post was held by the same canon who was also the Rector of St Margaret's, Westminster (Parliament's parish church.) In 2010, Bercow appointed Rose Hudson-Wilkin, Vicar of Dalston and Haggerston as his chaplain; she remains a vicar as well as Speaker's Chaplain. Hudson-Wilkin was the first chaplain appointed not to be a canon of Westminster. 
On normal sitting days, the Speaker wears a black silk lay-type gown (similar to a Queen's Counsel's gown) with (or without, in the case of Bercow) a train and a mourning rosette (also known as a 'wig bag') over the flap collar at the back.
The current Speaker, John Bercow, no longer wears the traditional court dress outfit, which included knee breeches, silk stockings and buckled court shoes under the gown, or the wig. Betty Boothroyd first decided not to wear the wig  and Michael Martin chose not to wear knee breeches, silk stockings or the traditional buckled shoes, preferring flannel trousers and Oxford shoes.  Bercow chose not to wear court dress altogether in favour of a lounge suit, as he felt "uncomfortable" in court dress    (he wore morning dress under the State Robe at State Openings). As seen at the 2015 State Opening of Parliament, Bercow further toned down the state robe by removing the gold frogging on the sleeves and train, so that it now resembles a pro-chancellor's robe at certain universities. However, he returned to wearing the traditional robe in 2016.
Current Speaker and Deputy Speakers
- List of Speakers of the House of Commons of England (up to 1707)
- List of Speakers of the British House of Commons
- List of peerages created for Speakers of the House of Commons
- Presiding Officer of the National Assembly for Wales
- Presiding Officer of the Scottish Parliament
- Speaker of the Northern Ireland Assembly
- Speaker (politics)
- Speaker's State Coach