Official Opposition (UK)

The Official Opposition, fully Her Majesty's Official Opposition, comprises the largest political party or parliamentary group in opposition to the government in the House of Commons and the House of Lords, i.e. typically the second-largest party in the Parliament of the United Kingdom. The Leader of the Opposition heads a 'Shadow Cabinet' of senior Opposition politicians, each of whom scrutinises the work of equivalent government ministers. Since September 2010 the Labour Party has formed the Opposition, first with Ed Miliband as Leader of the Opposition, then Jeremy Corbyn (since 2015).

House of Commons

When the Opposition party wins a general election, it is expected that it will be formally invited to form a new government, and the party leader (usually the Leader of the Opposition in the House of Commons) will become the next Prime Minister. In contrast, a new Leader of the Opposition emerges immediately, without any formal ceremony - for example, when John Major resigned as Prime Minister in 1997 following an election defeat, he left Buckingham Palace as the Leader of the Opposition, as his party was now second-placed in terms of number of seats in Parliament. By contrast, when Gordon Brown stepped down as Prime Minister, he did not become Leader of the Opposition due to his resignation from the leadership of the second-placed Labour Party.

The Opposition receives the largest share of 'Short Money' (state funding); for example, in 2005-2006 the Conservatives received over £4 million in various expenses, with money also spent on vehicles and security. In other words, in the British parliamentary system, the public pays political parties to oppose the elected government.

As a potential Prime-Minister-in-waiting, the Leader of the Opposition's most prominent parliamentary duty is the weekly appearance at a debate known as 'Prime Minister's Questions', in which the Leader of the Opposition faces the Prime Minister over the floor of the House of Commons. The Opposition Leader asks six questions, which are not made available to the Prime Minister's office in advance. Another way in which parliamentary activities present the Opposition as a potential future government is at the State Opening of Parliament, where the Shadow Cabinet joins senior members of the government at the head of a procession from the Commons to the House of Lords.

Shadow Cabinet

The Leader of the Opposition heads a group of senior party politicians who 'shadow' the work of their opposite numbers in government. These appointments are made by the Opposition leader when the Conservative Party is in opposition, while in the Labour Party where the posts are elected; this generally obligates an incoming Labour prime minister to appoint them as ministers, those not necessarily in the positions they had been shadowing.