Constitutional convention (political custom)
A constitutional convention is an informal and uncodified tradition that is followed by the institutions of a state. In some states, notably those Commonwealth of Nations states that follow the Westminster system and whose political systems derive from British constitutional law, most government functions are guided by constitutional convention rather than by a formal written constitution. In these states, actual distribution of power may be markedly different from those the formal constitutional documents describe. In particular, the formal constitution often confers wide discretionary powers on the head of state that, in practice, are used only on the advice of the head of government, and in some cases not at all.
Not to be confused with Constituent assembly.
Some constitutional conventions operate separately from or alongside written constitutions, such as in Canada since the country was formed with the enactment of the Constitution Act, 1867. In others, notably the United Kingdom, which lack a single overarching constitutional document, unwritten conventions are still of vital importance in understanding how the state functions. In most states, however, many old conventions have been replaced or superseded by laws (called codification).
Historical entities often had strong emphasis on constitutional convention. For example the constitution of the Roman Republic was codified comparatively late in its development and relied for its functioning on traditions and a shared moral code called mos maiorum. In the Holy Roman Empire such important issues as who could elect the emperor were entirely uncodified before the Golden Bull of 1356 and remained subject to a certain degree of interpretation well afterwards.
Origins[edit]
Constitutional conventions arise when the exercise of a certain type of power, which is not prohibited by law, arouses such opposition that it becomes impossible, on future occasions, to engage in further exercises of this power. For example, the constitutional convention that the Prime Minister of the United Kingdom cannot remain in office without the support of a majority of members of the House of Commons is derived from an unsuccessful attempt by the ministry of Robert Peel to govern without the support of a majority in the House, in 1834–1835.
Enforceability in the courts[edit]
Constitutional conventions are not, and cannot be, enforced by courts of law. The primary reason for this, according to the Supreme Court of Canada in its 1981 Patriation Reference, is that, "They are generally in conflict with the legal rules which they postulate and the courts may be bound to enforce the legal rules."[3] More precisely, the conventions make certain acts, which would be permissible under a straightforward reading of the law, impermissible in practice. The court ruled that this conflict between convention and law means that no convention, no matter how well-established or universally accepted, can "crystallize" into law, unless the relevant parliament or legislature enacts a law or constitutional amendment codifying that convention.[4] This principle is regarded as authoritative in a number of other jurisdictions, including the UK.
Some conventions evolve or change over time. For example, before 1918 the British Cabinet requested a parliamentary dissolution from the monarch, with the Prime Minister conveying the request. Between 1918 and 2011,[5] Prime Ministers requested dissolutions on their own initiative, and were not required to consult members of the Cabinet (although, at the very least, it would have been unusual for the Cabinet not to be aware of the Prime Minister's intention). In 2024 Prime Minister Rishi Sunak reportedly announced his intention to hold an early election in July 2024 without even informing most of his cabinet prior to the announcement.[6][7]
However, conventions are rarely ever broken. Unless there is general agreement on the breach, the person who breaches a convention is often heavily criticised, on occasions leading to a loss of respect or popular support.