The UK is a constitutional monarchy, which in basic terms means that there is a royal family with the king or queen in the role as Head of State. In a constitutional monarchy, the Head of State does not change after there has been an election. They are a point of continuity and have an ambassadorial role, with many ceremonial and official duties. However, they have little political power and do not make or pass laws. That is left to three other constitutional elements: the executive, the legislature and the judiciary.
Executive, legislature and judiciary
These are the bodies within the UK that formulate, pass and enforce legislation. It is a relatively common structure within democratic systems. The executive puts forward propositions for new laws and formulates the budget, the legislature debates and either approves or rejects the new laws, and the judiciary enforces the laws.
This directly translates as:
executive = the government, led by the Prime Minister and his Cabinet
legislature = the Westminster Parliament, made up of two houses: the House of Commons and the House of Lords
judiciary = the court system, led by the Lord Chief Justice
Critics of the UK system point to the fact that there is no clear separation of powers between the three institutions. That is to say, there are overlaps at each level. The members of the executive are also members of the legislature: our Prime Minister, Home Secretary etc. are both members of government and MPs. Judges who are peers in the House of Lords are members of both the legislature and judiciary. It is even possible to be a member of all three at the same time, if you are a judge in the House of Lords who is chosen by the Prime Minister to join his Cabinet (as was the case with Lord Falconer, as part of Tony Blair’s government).
How is the government formed?
In the UK, a new executive, or government, is formed after each General Election. It is up to the leader of the party who has won the greatest number of seats to form the government.
If any political party has won a clear majority, it is straightforward: the party leader will take up the post of Prime Minister and choose the other members of Cabinet and junior ministers from within his or her own party.
In outcomes where there is no clear majority, the party leaders have to seek to attain support from the majority of the legislature from their own party and others. This can either be through coalition, as was the case following the 2010 General Election, with the Conservatives and Liberal Democrats jointly forming a government and sharing Cabinet and ministerial posts between them, or through “confidence and supply”. In the case of confidence and supply, the executive is made up of one party, but they agree support with other parties within the legislature. This happened in 1977 with the “Lib-Lab pact”, where Callaghan’s Labour government arranged to adopt a small number of Liberal policies in exchange for the Liberals committing to support the Labour government in a confidence vote.
Due to convention, the appointment of the Prime Minister and his or her new government has to be formally approved by the Queen, as she remains the Head of State.