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Source: Conventions

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  • conventions are a non legal source of UK constitution
  • tend to govern relationships between branches of State – executive (Crown and Government), legislature and judiciary
  • extend principles in Bill of Rights 1689
  • regulating the processes and mechanics of Government, consistent with concept of democratic legitimacy


  • constitutional conventions are not rigid and difficult to define
  • AV Dicey: .. The other set of rules consist of conventions, understandings, habits or practices which, though they may regulate the conduct of several members of the sovereign power, of the Ministers, or of other officials, are not in reality laws at all since they are not enforced by the courts. This portion of constitutional law may, for the sake of distinction, be termed ‘the conventions of the constitution’, or constitutional morality... (Introduction to the Study of the Law of the Constitution (1885))
  • KC Wheare: .. a binding rule, a rule of behaviour accepted as obligatory by those concerned in the working of the constitution.. (Modern Constitutions (1951))
  • Sir Ivor Jennings: .. the short explanation of the constitutional conventions is that they provide the flesh that clothes the dry bones of the law; they make the legal constitution work; they keep it in touch with the growth of ideas... (The Law and the Constitution (1959))
  • Geoffrey Marshall and Grahame Moodie: .. rules of constitutional behaviour which are considered to be binding by and upon those who operate the Constitution but which are not enforced by the law courts... nor by the presiding officers in the Houses of Parliament... (Some Problems of the Constitution (1971))
  • tends be broad recognition of the content of some conventions
  • including: monarch appoints leader of majority party of Commons as Prime Minister, rules ministers are individually and collectively responsible to Parliament and udges will remain politically impartial
  • usually seen as supplementary to laws but sometimes seem to override legal rules
  • by law monarch must approve Bills before they become an Act of Parliament, convention that tmonarch will not refuse Royal Assent to Bills, last time Queen Anne (Scottish Militia Bill 1707)
  • conventions should be viewed as ..non legal rules regulating the way legal rules shall be applied... (Marshall and Moodie)


  • usually unwritten so difficult to determine when they came into existence or a precise process of creation
  • Colin Munro: .. do not come from a 'certain' number of sources: their origins are amorphous... Nobody has the function of deciding whether conventions exist. There is no formal sign of their entitlement to be so regarded, as there are no agreed rules for deciding.. (Studies in Constitutional Law (1999))
  • most conventions seem to evolve as political procedures before they become recognised a constitutional convention
  • most conventions are created organically over time, especially those relating the role of the Crown
  • some can be seen as result of specific events - conventions that establish framework for relations between UK and Commonwealth countries set out in PStatute of Westminster 1931, after being agreed at a conference

Jennings Test

  • Jennings proposed a threefold test for the identification of conventions:
  • 1 What are the precedents?
  • 2 Did the actors in the precedents believe that they were bound by a rule?
  • 3 Is there a constitutional reason for the rule?
  • test can be used to decide whether a convention has come into existence or ceased to operate
  • three elements must be present if the convention is to be fully established
  • Supreme Court of Canada approved Jennings Test

    Re Amendment of the Constitution of Canada [1982]

    • Government proposed constitutional changes, written Canadian constitution did not require consent of provinces
    • convention that provinces agreement should be obtained prior before changes were made to the constitution
    • found: .. the main purpose of constitutional conventions is to ensure that the legal framework of the constitution will be operated in accordance with the prevailing constitutional values and principles of the period... Perhaps the main reason why conventions cannot be enforced by courts is that they are generally in conflict with the legal rules which they postulate and the courts are bound to enforce legal rules...
    • as a result of the decisionGovernment submitted alternative proposals which were approved by majority of provinces
    • decision is persuasive in UK
  • Munro has argued Jennings Test is inadequate: lack of clarity over who decides what is a sufficient constitutional reason and emphasises precedents not recognising some conventions are based on agreements


  • rules are not enforceable by the courts but seem to be largely obeyed
  • individual office holders may obey conventions to maintain legitimacy and an accept that by taking office there is implied agreement to follow conventions


  • Dicey argued ultimately a breach of convention would lead to a breach of law illustrated by referring to convention that Parliament must meet each year and if it failed to do so the authority for the maintenance of the army would lapse (under Article 6 of the Bill of Rights 1689)
  • Munro: .. the breach of a convention carries with it a destructive effect, which is absent with laws...
  • convention that is not adhered to does not necessarily cease to exist but may require future affirmation

Distinction from Laws

  • laws and constitutional conventions are interlinked but distinct
  • Creation

  • a law be found in an Act of Parliament or in a judicial decision
  • a convention is a practice that is observed from an undefined point
  • Certainty

  • a law is written in legislation or a judgment and therefore there is a level of certainty
  • most conventions are not written and therefore less easy to determine
  • parctice of convention on Ministerial Responsibility is vague but in comparison the rules of Royal Assent are more established
  • Alteration

  • a statute must be revised or a judicial decision overturned in order for a change in law to take place
  • a convention can evolve without any formal process
  • Enforceability

  • laws are enforceable by courts
  • conventions lack formal enforceability
  • Dicey constitutional conventions are .. not in reality laws at all since they are not enforced by the courts...
  • Marshall conventions .. are unlike legal rules because they are not the product of a legislative or a judicial process....
  • Breach

  • a breach of a law has a defined legal sanction but a breach in itself does not affect the validity of the law
  • a breach of a convention has no legal repercussion but may have a political impact
  • Munro argues a serious breach of a convention may challenge its effectiveness and even result in the overturning of the convention

Appointment of the Prime Minister

  • key constitutional conventions relates to appointment of the Prime Minister
  • role of the Monarch to appoint a Prime Minister, legally this can be whoever they choose
  • by convention it must be someone who commands the confidence of a majority in the House of Commons
  • precedent suggests that the Prime Minister must be either a member of a House of Parliament
  • since 1963 it has become a recognised convention that a Prime Minister should come from the House of Commons, in order to be accountable to the House
  • exception that a Prime Minister can hold office temporarily whilst not a MP during a General Election

Conventions and the Courts

  • constitutional conventions may not be strictly enforceable in courts, however, may still require consideration in cases

    R v Secretary of State for Home Affairs, ex p Hosenball [1977]

    • Court of Appeal declined to review Home Secretary's decision to deport a journalist in the interest of national security
    • Lord Denning: .. he is answerable to Parliament as to the way in which he did it and not to the courts here...

    R v Secretary of State for the Home Department, ex parte Cheblak [1991]

    • C sought judicial review of the Home Secretary's decision to deport him on the grounds of national security
    • again the court recognised existence of convention of Ministerial Responsibility, that a Minister is accountable to Parliament for their decisions

    Carltona v Commissioners of Works [1943]

    • C argued requisition of their factory was invalid
    • order requisitioning factory was made under wartime regulations had been signed by a civil servant on behalf of a Minister
    • signing such an order was a statutory power given to the Minister
    • Lord Greene: .. Constitutionally, the decision of such an official is, of course, the decision of the minister. The minister is responsible. It is he who must answer before Parliament for anything that his officials have done under his authority...
    • Carltona principle is derived from this case – a civil servant may exercise a statutory power on behalf of a minister even though the statute does not expressly allow the minister to delegate such exercise

    Attorney-General v Jonathan Cape [1976]

    • C, Attorney General, sought an injunction against the D, acting on behalf of deceased cabinet Minister Richard Crossman and Sunday Times
    • Crossman had kept a detailed diary documenting his time in the Cabinet
    • he wished to publish diary to challenge traditional secrecy of British Government and give public an insight into decision making
    • Crossman died before the diaries were published
    • after his death Sunday Times began to print extracts and executors of his will planned to publish diaries in full, in accordance with Crossman’s wishes
    • C argued convention of collective Cabinet responsibility was the issue
    • also that the convention was enforceable by the courts on the grounds of public interest
    • D contended convention is not a legal obligation which courts can enforce, except in national security cases
    • further if publication of Cabinet proceedings was contrary to the public interest it should be stated in legislation
    • court decided not enforce the convention of Cabinet secrecy by granting an injunction to prevent publication
    • held that in this case an injunction was unnecessary as the diaries could no longer be considered confidential, as ten years had passed
    • court acknowledged that in principle there is a legal obligation of confidentiality in relation to Cabinet proceedings
  • Statute and Convention

  • courts seem willing to acknowledge existence of conventions
  • conventions may indirectly give rise to legal obligations which the courts will enforce
  • conventions can be used in court to support arguments of law but cannot be used to contradict arguments of law
  • if an Act of Parliament was passed which is in breach of a convention, it may be an unconstitutional Act but the courts will not necessarily recognise it as illegal and refuse to apply the Act

    Madzimbamuto v Lardner Burke [1969]

    • Privy Council had to decide whether Parliament could lawfully legislate for Southern Rhodesia after that country had declared its independence
    • Government of Southern Rhodesia contended that there was a convention which required their consent before any UK legislation could apply to Southern Rhodesia
    • Lord Reid: .. It may be that it would be unconstitutional to disregard this convention. But it may also be that the unilateral Declaration of Independence released the United Kingdom from any obligation to observe the convention. Their Lordships in declaring the law are not concerned with these matters. They are concerned only with the legal powers of Parliament...
    • case advocates view that a convention has no legal effect in limiting legislative power of Parliament
  • Refusal to Enforce

  • judicial discretion in interpreting the law
  • could enable courts to place more or less weight on constitutional conventions in some circumstances
  • it seems courts have resisted doing so
  • conventions are formed by precedents set by institutions of Government not judiciary
  • important that there is no obligation for courts to enforce conventions and to do so would involve formal sanctions
  • issues would arise from trying to resolve conflicts between laws and conventions
  • if courts were to attempt to enforce constitutional conventions they would no longer be conventions or so distinct from laws

Critical Analysis

  • been suggested that conventions should be written to try to make them less flexible and more explicit
  • this creates possibility of conflict between actual practice and text of the convention
  • Ministerial Code, first published in 1992, does go some way to enunciating the constitutional conventions in relation to Ministerial Responsibility
  • uncertainty of conventions can be criticised
  • their flexibility can be seen as an advantage especially in allowing for political development, for example in relationship between Crown and Government
  • legal certainty required to satisfy concept of rule of law
  • rule of law can be seen as focussed on matters concerning individual liberty rather than constitutional mechanisms
  • enforcement by the courts has been raised as a possibility
  • this would blur separation of powers because it is the judiciary's role to resolve legal disputes and for executive to govern according to law
  • conventions can be seen as political practices with ability to evolve which would be altered completely if the courts became enforcer
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