Introduction
The orthodox departure’s point for analysing British constitution’s architecture is Bagehot’s famous claim that the “efficient secret” of constitution lies in “[a] close union, nearly complete fusion, of executive and legislative powers,” connecting link being the Cabinet. This aphorism has survived because it captures core feature of Westminster model. The government, under this model, is drawn from, sustains authority, and is answerable to parliament through mechanism of ‘responsible government’, specifically confidence convention and collective ministerial responsibility. This makes fusion not a defect of constitution to be rectified, but a design choice binding accountability and authority together, enabling efficient government meanwhile tethering it to representative chamber. Therefore, one can be tempted to conclude that UK’s constitutional strength lies in interdependence of institutions prized by Bagehot. However, constitution analysed by Bagehot has evolved and changed profoundly, and continues to do so. This makes any claim of fusion being an unalloyed strength must be evaluated considering modern separation, functional and partial, among institutions, rule of law demands, and growth of judicial review. The core question is whether fusion still delivers accountable, efficient, and responsible government without eroding safeguards that separation thesis seeks to secure.
Bagehot’s ‘Fusion’ Thesis and ‘Responsible Government’
The fusion thesis of Bagehot was based on political reality that elected House of Commons (“HC”) provides ministers and Cabinet, integrating administrative execution and law-making initiatives. Practically, fused system sought to streamline legislative implementation and policy creation. It envisaged that government, with majority, can make laws for its programme, engage in parliamentary debate, be accountable through questions and answers, and be removed from office without need for formal impeachment-style procedures. Fusion, therefore, was meant to create a seamless feedback system between the administering and being checked. In theory, it diminishes risks of deadlock, afflicting presidential systems having strict separation, because ministers are also party of the Parliament. It enables scrutiny at source through opposition debates, urgent questions, and hearings of select committees.
The historical context and nemesis of Bagehot’s idea of fusion is the American constitution in which its founders “wished to keep ‘the legislative branch absolutely distinct from the executive branch’” and felt that “to the effectual maintenance of such a separation, the exclusion of the President’s ministers from the legislature is essential.” Ultimately, formal arrangements on fusion or separation of legislature and executive powers – under presidential or parliamentary systems – for dispersing or concentrating power is “significantly a function of both political party and electoral systems in place.” Since this is subject to change, efficiency of fusion thesis has to be judged according to its legal foundations and change of politics (as analysed in subsequent sections).
Legal Foundations and Parliamentary Sovereignty
The UK’s peculiar settlement of rule of law and parliamentary sovereignty forms the doctrinal counterpact to the political fusion thesis. The omnipotence of parliament under independent judicial system was envisaged by Dicey. It minimized role for codification of separation of powers that courts could enforce by substantive judicial review. The political constitution that evolved privileged parliamentary control, through elections, conventions, and votes, as opposed to judicially-enforced restrictions on primary legislation. In this framework, fusion becomes source of strength keeping ultimate authority in democratic body and ensuring continuation of executive in office based on confidence of parliament. This enables rapid adaptation at constitutional level through convention and staute instead of formal constitutional amendment mechanisms.
Historical evolution of Fusion and Separation of Powers
Bagehot’s thesis may be termed as overstatement of the scope and degree of the fusion between the legislative and executive branches, but there is clear that “a fusion between a vote for an individual candidate and the party they represent has been a fact of political life since the 19th century.” This underlies the prevalence of ‘political constitutionalism’ – that is, parliament and government are not answerable to the courts through ‘substantive’ judicial review powers. It means complete democratic accountability for exercise of government powers through parliament and representative government - whereby ministers are answerable to their constituents through debates, question and answers, and most importantly, elections. The evolving nature of the constitution, politics, and government functions impacts separation of powers model prevalent in the Westminster system. It shows a trend towards stricter separation of powers to prevent abuse of power, while maintaining the fusion necessary for efficient operation of separation between branches.
The evolution of English constitution (primarily due to lack of complete formalization and codification) means that there is no fixed model of separation. The concentration and distribution of power in and within the parliamentary executive and other branches has been subject to change with greater formalization of institutions and enactment of ‘constitutional statutes’ as well as political developments. Gardbaum, commenting on Bagehot’s fusion argument, argues that changing political practices and institutional developments have eroded faith in the ability of fusion of powers to ensure sufficient check on government power and action.
Increasing Concentration of Power in the Executive
These developments necessitate re-think of separation. Hence, what worked in 1860s in Bagehot’s time may not make UK government more responsible. Garbaum recgonsies that this is not a sole English problem, but other constitutions have faced problems with political constitutionalism, such as in Canada and New Zealand. He traced elected representative’s independence and supremacy in government through cabinet and independent-minded MPs in Britain from 1832 until 1945. But over time, political parties dominated and disciplined members through whip system. It further led to ‘double concentration of power’ in the prime minister and handful of ministers has enabled executive overreach.
The executive overreach has been a serious, multidimensional issue in recent English history. Dominance of populist and strong politicians such as Tony Blair, Boris Johnson, and so on, have shown that not only the parliament but the cabinet can also be overreached by a single individual. Despite positive constitutional impact of increase in MP independence intensifying separation of powers, the ministerial-led executive overreach extends beyond personnel and function. It can threaten basic liberties and bypass democratic legitimacy and accountability through subordinated legislation and other powers.
For instance, Lord Sumption has severely criticized the manner in which the ministers suspended and restricted liberties in the Covid-19 times. It undermines rule of law that is now accepted to have substantive content involving guarantees and protection of fundamental liberties and rights. The tumultuous nature of political constitutionalism has led to upheaval in stability of governments evident from the rise in number of ministers reaching the prime minister office in the last decade, under the confidence convention - a key feature of fusion-based responsible government. At the very least, it does not inspire confidence in efficiency of the system. Even though elevation to the prime minister office and change of cabinets has not required any formal impeachment process, it has required few general elections. This is what can be meant by Kelly’s “[t]he slow death of the ‘Efficient Secret’…” attack on Bagehot’s thesis.
Miller and Cherry Cases and Fusion Thesis
In controversies when government is tested and held accountable, the judicial role becomes highly crucial. In Miller’s case, the UKSC disallowed ministers to use the prerogative power for change of domestic law and or create rights which is otherwise not sanctioned by parliament. In Miller (No 2)/Cherry case, the UKSC did not find the action of the prime minister to prorogue parliament as legal and constitutional as it would frustrate parliamentary scrutiny regardless of any reasonable justification. Broadly, these cases indicate intense debate of constitutional crisis between political frontiers and judiciary, but doctrinally it reflects a system where fusion lies at the heart when there is a matter of accountability. In fact, fusion is effective as long as it is subject or accountable to Parliament or law. The decisions actually provide that the executive’s authority is derived as well as constrained or limited by the legislature because of it’s sovereignty and the UKSC supervisory role of identifying and recognising legal limits on executive actions.
The two cases i.e. Miller and Miller/Cherry have evolved the judicial stance in respect of correlation between the executive, legislature and the judiciary. In Miller the UKSC prevented the executive from triggering Article 50 TEU unless parliament gave the approval. The significance of the decision is that it has maintained the judicial fragrance and recognised fusion of powers. The judicial intervention is essential to maintain distribution of authority. And the Miller/Cherry case further took this judicial oversight and maintained that the judiciary is an active constitutional guardian.
Rule of law and judiciary
The courts have also given due regard to constitutional fundamentals for the sake of citizens and making parliament to keep considering fused executive-legislative government in check. In the case of UNISON, the UKSC found fees of tribunal unlawful since it was found a hurdle in the way of seeking justice. It means rule of law is a way or manner to absolve legal redress. The UKSC in Evans case also rejected the action of Attorney General to veto the court’s decision of disclosure of information. In fact, the court hold out that the executive is subject to certain limits. It means courts maintain legality of executive actions. In another case, the House of Lords (HOL) issued declaration of incompatibility against detention provisions, demonstrating supremacy of parliament, but this shows that rule of law is subject to limitations. It is contended that judiciary acts a constitutional counterweight to balance and maintain precarious situations, and in respect of the UK situation it stabilises fusion and ensure that members of Commons despite having political leverage remains subject to legal challenges or accountability. They are not beyond law.
Threat of Executive dominance and fusion system
Fusion system at times risks parliamentary scrutiny of the executive, it is usually when there is a strong party discipline yet there is large majority in the House of Commons. In case of controlling both party and Cabinet, legislative oversight is under risk of being dull in legislative functions. Select Committees are less competitive in imposing consequences. Similarly, government’s proposal can lead to delays and insufficient changes. Yet, it is not because of separation of powers but there is practical imbalance i.e. fusion must be subject to intra-parliamentary checks otherwise, it will lead to dominance of executive body. there are mediating institutions which have developed to level up accountability such as role of select committees which interrogates Prime Minister including discussion on urgent questions. The House of Lords tend to have revising function in relation to legislative matters. In essence, fusion has strength which ties with the survival of the executive with respect to the confidence of a representative legislature. In addition, there are other formal and informal controls on the executive actions.
Conventions in relation to ministerial accountability are imperfect in nature yet structurally there are certain expectations engaged in it. Fusion is visible and everlasting. It is such a system that tends to ensure survival of the executive because of representative of legislature and maintains that correlation or nexus is subject to formal and informal controls.
Fusion in times of Constitutional Stress and Deadlocks
In constitutional crisis or stress, fusion is apparent. For instance, in 2019, the Prime Minister desired to prorogue parliament by acting on royal prerogative which had effect of disturbing or frustrating Parliament’s scrutiny. The manner of fusion is legal as well as political in nature consider the issues of parliamentary accountability and ministerial response. In this way, proceedings and committees of parliament could likely to continue its operation without compromising the political constitution. Yet, fusion is not a case of creating any constitutional breakdown or crisis, it provides or set for precondition which help in fast correction in case of any overreach of legal boundary. It is because of fusion that the Commons could call for accountability of ministers and legislate on matters accordingly and in a quick manner. And various political scientists endorse fusion for its flexibility which is otherwise less prevalent in rigid regimes.
Creating a balanced constitutional settlement
However, the UK’s position is not what Bagehot analysed fusion since the UK recognise separating certain institutions of state. By introducing the Constitutional Reform Act 2005 (“CRA”), it has become clear that there is structural independence of the judiciary. Discussions with regard to the office of the Lord Chancellor, control on judicial appointments, and the UKSC’s role identify the fusion at the apex level especially when the HOL was the main judicial body, yet it was not constitutionally efficient. In lieu of the CRA, the judiciary becomes more independent. And the leadership is separated from the Cabinet and need not be dependent on the Cabinet. It is not like repudiation of fusion; in fact, it is an endorsement where political powers and adjudication both remain intact. This is called institutional separation of powers. As a result, the fusion in the post CRA has enhanced further by separating judiciary.
Devolution & Fusion
In respect of territorial pluralism and administrative specialisation, fusion coexists well. By devolution the UK has given way to new legislatures and executives such as in Scotland, Northern Ireland, and Wales. But it is viable because of fused relationships per accountability and confidence along-with preservation of Sovereignty of Parliament. The nexus of Cabinet with Commons remains an organising principle of the Parliament in Westminster. Yet, it is subject to multi-level governance. Although critics find the fusion as less coherent and effective, yet there is efficiency in fusion system and becomes a tool of political accountability within each pair i.e. legislature-executive, and executive-judiciary. Yet, there is independence of the judiciary and stability of legal order. This balance provides resilience to the UK constitution.
It has been revealed by the two cases i.e. Miller and Miller/Cherry that the fusion of powers does not provide for unlimited course of actions by executive. In fact, the strength of the UK’s constitution is in this fused arrangement of institutions, with judiciary has an assertive role which can intervene when the balance is tilted. However, critics find the two cases as a case of shift toward more separatist approach, but some other find the fusion model naturally evolving, by catering to contemporary challenges. The obiter in the case of Jackson v Attorney General also hinted on judicial intervention as constitutional fundamentals in extreme cases. The functional separation is highly proactive whenever principles of constitution are under threat.
Conclusion
On balance, based on the analysis, the fusion thesis provides great strength to UK’s constitution, but not as suggested by unqualified celebration of Bagehot. Its strength is only provided if it is disciplined and properly restrained. It requires separation thesis for its operationalisation. The energetic integration of executive-legislative must be answerable to House of Commons and be perennially bounded by law. The capacity of Cabinet to make laws and govern exclusively emerges from its embedded nature in the HC. But its ability to remain legal and respect rights depends on the readiness of courts to enforce and protect constitutional principles. The developments in CRA are not importation of legal culture of American-style strict separation. It is an adjustment made by UK settlement to prevent political and executive overreach by making these branches subject to a truly independent judicial organ. Therefore, the quality of genius of Westminster Model is not strict separation for sake of separation but careful integration of fused political system with legal restraint. This reconciliation as shown in Miller cases, UNISON, GCHQ, and other cases, and by evolving institutional and political reforms clarifying judicial independence exemplifies the endurance of an uncodified constitution. Hence, fusion provides for accountability and adaptative energy but the laws provide remedy and boundaries. It is this fusion of separation and fusion thesis that gives the constitution its strength.
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