House of Commons of the United Kingdom

Although the House of Commons does not formally elect the prime minister, by convention and in practice, the prime minister is answerable to the House, and therefore must maintain its support. In this way, the position of the parties in the House is of overriding importance. Thus, whenever the office of prime minister falls vacant, the monarch appoints the person who has the support of the house, or who is most likely to command the support of the house—normally the leader of the largest party in the house—while the leader of the second-largest party becomes the leader of the Opposition. Since 1963, by convention, the prime minister has always been a member of the House of Commons, rather than the House of Lords.

The Commons may indicate its lack of support for the government by rejecting a motion of confidence or by passing a motion of no confidence. Confidence and no confidence motions are phrased explicitly: for instance, "That this House has no confidence in Her Majesty's Government." Many other motions were until recent decades considered confidence issues, even though not explicitly phrased as such: in particular, important bills that were part of the government's agenda. The annual Budget is still considered a matter of confidence. When a government has lost the confidence of the House of Commons, the prime minister is obliged either to resign, making way for another MP who can command confidence, or request the monarch to dissolve Parliament, thereby precipitating a general election.

Since 1990, almost all cabinet ministers, save for three whose offices are an intrinsic part of the House of Lords, have belonged to the Commons.

The House of Commons formally scrutinises the Government through its Committees and Prime Minister's Questions, when members ask questions of the prime minister; the house gives other opportunities to question other cabinet ministers. Prime Minister's Questions occur weekly, normally for half an hour each Wednesday. Questions must relate to the responding minister's official government activities, not to his or her activities as a party leader or as a private Member of Parliament. Customarily, members of the Government party/coalition and members of the Opposition alternate when asking questions. Members may also make inquiries in writing.

Since the 17th century, government ministers were paid, while other MPs were not. Most of the men elected to the Commons had private incomes, while a few relied on financial support from a wealthy patron. Early Labour MPs were often provided with a salary by a trade union, but this was declared illegal by a House of Lords judgement of 1909. Consequently, a resolution was passed in the House of Commons in 1911 introducing salaries for MPs.

The modern chamber, which opened following post-war reconstruction in 1950.
The old House of Commons chamber, showing dark veneer on the wood, which was purposely made much brighter in the new chamber.
The Speaker presides over debates in the House of Commons, as depicted in the above print commemorating the destruction of the Commons Chamber by fire in 1834.

At the beginning of each new parliamentary term, the House of Commons elects one of its members as a presiding officer, known as the Speaker. If the incumbent Speaker seeks a new term, then the house may re-elect him or her merely by passing a motion; otherwise, a secret ballot is held. A Speaker-elect cannot take office until she or he has been approved by the Sovereign; the granting of the royal approbation, however, is a formality. The Speaker is assisted by three Deputy Speakers, the most senior of whom holds the title of Chairman of Ways and Means. The two other Deputy Speakers are known as the First and Second Deputy Chairman of Ways and Means. These titles derive from the Committee of Ways and Means, a body over which the chairman once used to preside; even though the committee was abolished in 1967, the traditional titles of the Deputy Speakers are still retained. The Speaker and the Deputy Speakers are always members of the House of Commons.

During debates, Members may speak only if called upon by the Speaker (or a Deputy Speaker, if the Speaker is not presiding). Traditionally, the presiding officer alternates between calling Members from the Government and Opposition. The Prime Minister, the Leader of the Opposition, and other leaders from both sides are normally given priority. All Privy Counsellors used to be granted priority; however, the modernisation of Commons procedure in 1998 led to the abolition of this tradition.

When the debate concludes, or when the closure is invoked, the motion is put to a vote. The house first votes by voice vote; the Speaker or Deputy Speaker puts the question, and Members respond either "Aye!" (in favour of the motion) or "No!" (against the motion). The presiding officer then announces the result of the voice vote, but if his or her assessment is challenged by any member or the voice vote is unclear, a recorded vote known as a division follows. The presiding officer, if she or he believes that the result of the voice vote is clear, may reject the challenge. When a division occurs, members enter one of two lobbies (the "Aye" lobby or the "No" lobby) on either side of the chamber, where their names are recorded by clerks. A member who wishes to pointedly abstain from a vote may do so by entering both lobbies, casting one vote for and one against. At each lobby are two tellers (themselves members of the house) who count the votes of the members.

Once the division concludes, the tellers provide the results to the presiding officer, who then announces them to the house. If the votes are tied, the Speaker or Deputy Speaker has a casting vote. Traditionally, this casting vote is exercised to allow further debate, if this is possible, or otherwise to avoid a decision without a majority (e.g. voting 'No' to a motion or the third reading of a bill). Ties rarely occur: more than 25 years passed between the last two ones in July 1993 and April 2019. The quorum of the House of Commons is 40 members for any vote, including the Speaker and four tellers. If fewer than 40 members have participated, the division is invalid.

Formerly, if a member sought to raise a point of order during a division, suggesting that some of the rules governing parliamentary procedure are violated, he was required to wear a hat, thereby signalling that he was not engaging in debate. Collapsible top hats were kept in the chamber just for this purpose. This custom was discontinued in 1998.

The British Parliament uses committees for a variety of purposes, e.g., for the review of bills. Committees consider bills in detail, and may make amendments. Bills of great constitutional importance, as well as some important financial measures, are usually sent to the "Committee of the Whole House", a body that includes all members of the Commons. Instead of the Speaker, the chairman or a Deputy Chairman of Ways and Means presides. The committee meets in the House of Commons Chamber.

Most bills were until 2006 considered by standing committees, which consisted of between 16 and 50 members. The membership of each standing committee roughly reflected the strength of the parties in the House. The membership of standing committees changed constantly; new Members were assigned each time the committee considered a new bill. The number of standing committees was not limited, but usually only ten existed. Rarely, a bill was committed to a Special Standing Committee, which investigated and held hearings on the issues raised. In November 2006, standing committees were replaced by public bill committees.