While the United Kingdom does not have a codified constitution that is a single document, the collection of legal instruments that have developed into a body of law known as constitutional law has existed for hundreds of years.
As part of this uncodified British constitution, constitutional conventions play a key role. Some rules that are observed by the various constituted parts though they are not written in any document having legal authority; there are often underlying enforcing principles that are themselves uncodified.
Conventions are often thought of as "unwritten" but sometimes conventions are recorded in writing e.g. the Cabinet Manual, the Ministerial Code. Similarly conventions are often thought of as evolving over time but they can sometimes be created at a specific moment in time e.g. the Salisbury Convention.
Examples include:
Treaties, although ratified using Royal Prerogative, will not be ratified until the passing of a suitable statute law by Parliament. This is necessary if the treaty requires an amendment to domestic law, affects the rights of private individuals, requires public expenditure, grants the Crown additional powers, or cedes territory. Examples include extradition treaties, double taxation treaties, and reciprocal social-security treaties.The monarch will accept and act on the advice of their ministers, who are responsible to Parliament for that advice; the monarch does not ignore that advice, except when exercising Reserve powers.The Prime Minister of the United Kingdom is the leader of the party (or coalition of parties) with an absolute majority of seats in the House of Commons and therefore most likely to command the support of the House of Commons.All money bills must originate in the House of Commons.The monarch will grant a dissolution of Parliamentif requested (1832 to 2011 – the Lascelles Principles in 1951 informally outlined the principles and issues that might lead to a refusal of a dissolution).The Prime Minister alone advises the monarch on a dissolution of Parliament (1918 to 2011).These conventions were implicitly ended by the Fixed-term Parliaments Act 2011, which removed dissolution of Parliament from the Royal Prerogative altogether.The monarch grants the Royal Assent to all legislation – sometimes characterised as all legislation passed in good faith. It is possible that ministers could advise against giving consent, as happens with the Crown dependencies (convention since the early 18th century – previously monarchs did refuse or withhold the Royal Assent).The Prime Minister should be a member of either House of Parliament (between the 18th century to 1963).In 1963 it was amended to the effect that no Prime Minister should come from the House of Lords. When the last Prime Minister peer, the Earl of Home, took office he renounced his peerage, and as Sir Alec Douglas-Homebecame an MP.The Prime Minister can hold office temporarily whilst not a Member of Parliament, for example during a General Election or in the case of Douglas-Home, between resigning from the Lords and being elected to the Commons in a by-election.All Cabinet members must be members of the Privy Council, since the cabinet is a committee of the council. Further, certain senior Loyal Opposition shadow cabinet members are also made Privy Counsellors, so that sensitive information may be shared with them "on Privy Council terms".[1]The House of Lords should not reject a budget passed by the House of Commons. This was broken controversially in 1909 by the House of Lords, which argued that the Convention was linked to another Convention that the Commons would not introduce a Bill that "attacked" peers and their wealth. The Lords claimed that the Commons broke this Convention in Chancellor of the Exchequer David Lloyd George's budget, justifying the Lords' rejection of the budget. The Commons disputed the existence of a linked convention. As a consequence, the Lords' powers over budgets were greatly lessened by the Parliament Act 1911.During a General Election, no major party shall put up an opponent against a Speaker seeking re-election. This convention was not respected during the 1987 General Election, when both the Labour Party and the Social Democratic Party fielded candidates against the Conservative Speaker, Bernard Weatherill, who was MP for Croydon North East. The Scottish National Party (SNP) does stand against the Speaker if he or she represents a Scottish Constituency, as was the case with Michael Martin, Speaker from 2000 to 2009.[2]The Westminster Parliament will only legislate on reserved matters. It will not legislate on non-reserved matters ("devolved matters") without first seeking the consent of the Scottish Parliament or Welsh Assembly (since 1999, the Sewel convention, later renamed to Legislative Consent Motions).The House of Lords shall not oppose legislation from the House of Commons that was a part of the government's manifesto (the Salisbury Convention).Ministers of the Crown are individually and collectively responsible to Parliament.Ministers are almost always members of either the House of Commons or the House of Lords.Parliament must be summoned to meet at least once each year.Judges shall not play an active part in political life.Members of Parliament shall not criticize the judiciary.The opinion of the Law Officers of the Crown is confidential.Advice of the prime minister or the cabinet — who are then accountable to Parliament for the decision — is required for the Royal Prerogative to be exercised. References Parliamentary briefing – the Privy Council, accessed 20 June 2012
Marshall and Moodie have defined conventions
As .. rules of constitutional behaviour which are considered to bebinding by and upon those who operate the constitution but which are not enforced by the courts... nor by the presidingofficers in the Houses of Parliament.
A constitutional convention is a non-legal rule which imposes an obligation on those bound by the convention, breach violation of which will give rise to legitimate criticism; and that criticism will generally take the form of accusation of
unconstitutional conduct.
The Queen will appoint as Prime Minister the leader of the political party with the majority of seats in the House of Commons and ministers must be members of either House of the Parliament are the examples of constitutional conventions. Conventions relating to the Cabinet system Prima facie the Ministry is entitled to continue in the office as long as it enjoys the confidence of the majority party in the Commons. But if it is out- voted on a major issue or if a vote of con confidence is passed, then it is bound to resign.
1. The Ministry is collectively responsible to Parliament for the
general conduct of the affair of the country.
2. The Cabinet should not advice, the Crown to declare war or
to make peace or conclude a treaty unless there is sufficient ground for them to believe that Commons approve of such a
measure. ( Conventions regulating the relations between the House of
Lords and the House of Commons and the proceedings in Parliament.
According to Dicey, the following conventions have grown up regulating the relations between the two Houses.
1. In case of a conflict between the two Houses, the will of the House of Commons must prevail.
2. Peers, who do not hold or have not held high judicial offices, do not attend when the House of Lords is sitting as the highest Court of Appeal.
3. Proposals involving the expenditure of public money may only be introduced on behalf of the Crown by a Minister in the
House of Commons.
4. The businesses of the House of Commons is rearranged informally "behind the Speaker's Chair", between the leader
of the House and the leader of the Opposition.
5. Political parties Parliamentary are represented Committees in proportion to the number of their supporters in the House.
