backbench MP, backbencher; back benches: for example: ‘Backbencher John Smith is seen as a rising star’, ‘a backbench conspiracy’, ‘there is concern on the back benches about the behaviour of the Prime Minister’.
Bill, Act, White Paper (draft Bill), Green Paper (discussion document), Private Member’s Bill: Traditionally all capped at every mention.
Cabinet, Cabinet ministers; Minister for Children, but ministers and ‘a ministerial aide’; Home Secretary, but former home secretary; Prime Minister and Deputy Prime Minister but acting/former prime minister.
committees: The Select Committee on Transport, the Standing Committee on Wines, both subsequently ‘the committee’. If you are using plurals, it is ‘the select committees’ (l/c). And please do not say that every single committee is ‘influential’.
General Election: Conventionally this takes caps, but ‘the election’. Lower case for local elections and by-elections.
Government: Capped if talking about the regime currently in power as a decision-making entity, eg ‘The Government will decide on Tuesday’, but l/c in all other contexts, such as ‘a government-backed organisation’ or foreign governments.
House of Lords: Is composed of hereditary peers and life peers. Life peers may belong to a party or be non-political. They are created Baron or Baroness and usually use their own surname, followed by ‘of (place name)’, such as Baron Sugar of Clapton in the London Borough of Hackney. At the second mention a man is called Lord, a woman Lady. If a life peer chooses to use two names, they must be hyphenated, for example Andrew Lloyd Webber (no hyphen) became Lord Lloyd-Webber of Sydmonton. Wives become ‘Lady Surname’ but husbands of women life peers do not benefit from a title. Children of life peers are entitled to style themselves ‘The Honourable', usually shortened to ‘The Hon’. The title dies with the holder and cannot be inherited.
Left-wing, Right-wing (adjectives), ‘the Left of the party’ or ‘the Left wing of the party’, ‘he is on the far Left’, ‘the far-Right grouping’.
No 10 Downing Street, No 10, or Number Ten. Not ‘Number 10’.
Parliament, but parliamentary.
parliamentary candidates: A person chosen by a constituency party to stand at the next General Election is a prospective parliamentary candidate (l/c) until the election is called, when formal nominations are submitted and the person becomes the parliamentary candidate (or candidate) for the seat.
parties: Specific political parties take the cap P, so the Labour Party, the Conservative Party, but ‘all the parties agreed . . . ’ Tory/Tories is acceptable for the Conservative party. The full name of Liberal Democrats can be shortened to LibDem/s or Lib Dem/s, with a space or without as you prefer.
party conferences: Traditionally, those attending are known as Conservative or LibDem representatives and Labour delegates.
Prime Minister: Don’t say ‘Prime Minister David Cameron’, but do your readers the courtesy of assuming that they know who is Prime Minister. Use either ‘David Cameron’ or ‘the Prime Minister’ at the first reference, then the reverse at the next. After that use ‘Mr Cameron’, ‘the Prime Minister’ or ‘the Premier’ (caps) at whim or fancy.
Privy Council, but Privy Counsellor (some authorities give Privy Councillor, but Counsellor is the one preferred by the Privy Council itself).
Serjeant at Arms (no hyphens) is a parliamentary official, not a political post. So is Black Rod.
Shadow Cabinet: You can say either ‘Shadow home secretary’ or ‘Labour home affairs spokesman’.
councillors: Do not use ‘Councillor John Smith’ (or, even worse, ‘Cllr John Smith’). Say: ‘A member of the council, John Smith’ or ‘council member John Smith’ and subsequently Mr Smith. These days councillors tend to have fancy job titles such as cabinet member for waste disposal – all lower case please.
Mayors (1): Most boroughs and cities have a mayor (l/c), a ceremonial post whose holder is elected by councillors for a term of a year. In a number of cities, the post is called Lord Mayor (caps). If the holder is a woman, she is also called a mayor or Lord Mayor. Mayors may appoint a consort for his or her term of office, usually a spouse. A mayor’s female consort is called a mayoress, a Lord Mayor’s is a Lady Mayoress. Note that mayoress or Lady Mayoress is not the term for a female mayor or Lord Mayor. A male consort of either a male or female mayor or Lord Mayor is the mayor's consort or Lord Mayor's consort. I am not sure about lesbian couples, but I think the partner would also be a mayor's consort or Lord Mayor's consort. Presumably they could choose their own styles.
Mayors (2): A number of large cities have a directly elected Mayor (cap), a political post whose holder is chief executive of the local authority for a fixed term of four years. If the city already has a ceremonial Lord Mayor, the two posts may co-exist.
European courts: the European Court of Justice, which sits in Luxembourg, deals with European Union law. Its decisions are binding on British courts. The European Court of Human Rights sits in Strasbourg and is not part of the EU, therefore do not use ‘EU’ in copy or headings. Its jurisdiction is recognised by 47 European states, including Great Britain, which have undertaken to honour its judgments. Although the court’s findings are not binding, in practice they are almost always accepted.
President Clinton/Bush: Former US presidents are commonly referred to as President for life. For presidents of all countries, use full title the first time, then ‘Mr’, ‘Mrs’ or ‘the President’ (cap); presidents in general are l/c.
bloc is the word for a group with common policies, not block.
socialist, socialism (l/c), except Socialist Workers’ Party.