Montesquieu’s nightmare

How the state consumes the separation of powers

23 December 2024

The separation of powers is a system of governance in which the responsibilities of government are divided among three distinct branches: the legislative, the executive, and the judiciary. Each branch has its own specific duties to prevent any single group or individual from holding too much power. The legislative branch makes the laws, the executive branch enforces them, and the judiciary interprets them. This division is supposed to ensure a system of checks and balances, where each branch limits the power of the others, maintaining accountability and protecting individual freedoms.

The concept of the separation of powers was famously articulated by the French political philosopher Montesquieu in his 1748 work The Spirit of the Laws. Montesquieu argued that dividing governmental power among separate branches would safeguard liberty and prevent tyranny. His ideas significantly influenced the framers of the US Constitution, who built a system of checks and balances into the federal government. Over time, this principle has become central to political theory and practice, particularly in liberal democracies around the world, where it is often adapted to suit different constitutional frameworks.

The separation of powers is widely regarded as a cornerstone of modern liberal democracy because of the safeguards it supposedly provides for fairness, accountability, and the rule of law. Ensuring that no single branch dominates the others, the theory goes, will help to protect citizens’ rights and freedoms. This system is also supposed to foster transparency and trust in government by requiring cooperation and compromise between branches. In a liberal democracy, the separation of powers guards against authoritarianism and creates a stable framework for resolving conflicts and upholding justice.

Or so the defenders of democracy like to maintain. In reality, the separation of powers is more honoured in the breach than in the observance. Even in advanced democracies like the US and the UK, a variety of countervailing forces tend to overwhelm the branch-based design of the separation of powers almost completely, preempting the political dynamics that are supposed to provide each branch of government with a will of its own. The separation of powers may sound fine in theory, but in practice the interplay of opposing political, institutional, and social forces undermines any real-world application. Partisan polarisation, bureaucratic expansion, executive overreach, and the growing complexity of global and domestic politics have all contributed to a significant erosion of the principle’s effectiveness.

From separation to mingling

The rise of partisan polarisation has blurred the lines between government branches, particularly in systems like the United States. When one political party controls both the executive and legislative branches, such as during the Trump presidency with a Republican Congress in 2017–2018 or the upcoming second Trump administration, the checks and balances intended to prevent abuse of power weaken. In such cases, Congress often acts as an enabler of the president’s agenda rather than as an independent check on executive authority. Conversely, when partisan divisions result in a split government, the separation of powers can lead to legislative gridlock rather than meaningful accountability. Meanwhile, the increasing power of unelected bureaucratic agencies further complicates the traditional model of separation. Regulatory bodies like the Environmental Protection Agency (EPA) or the Federal Reserve in the US consolidate legislative, executive, and judicial functions, creating and enforcing rules while adjudicating disputes — a process that lies outside the original framework of checks and balances.

Other structural factors further undermine the separation of powers. Judicial overreach, where courts shape policy through activism, and judicial deference, where courts fail to check executive actions, both disrupt the balance of power. Cases like Bush v. Gore (2000) and Citizens United v. FEC (2010) illustrate the judiciary’s policy making influence in the US, while the UK Supreme Court’s role in the 2019 Miller/Cherry prorogation case highlights the contested boundaries of judicial intervention. Modern executives also bypass legislative oversight through executive orders and prerogative powers. For example, US presidents increasingly rely on executive orders and emergency powers to advance their agendas (such as Trump’s border wall funding or Biden’s pandemic relief policies), while UK prime ministers have exploited royal prerogative powers for decisions like military intervention (e.g., Iraq in 2003) without direct parliamentary approval. Parliamentary systems like that of the UK often see the executive dominate the legislature through strict party discipline and control of the legislative agenda, further undermining the independence of Parliament. Prime Minister’s Questions (PMQs), while ostensibly an accountability mechanism, is often criticised as performative rather than substantive.

The challenges extend beyond domestic politics. Globalisation and external constraints imposed by international organisations and trade agreements frequently bypass traditional separation of powers. For instance, disputes resolved by bodies like the World Trade Organisation (WTO) or executive agreements made in global forums often operate without sufficient legislative oversight. Similarly, the influence of media and public opinion acts as an informal check on all branches, sometimes bypassing institutional processes entirely, as seen during the US civil rights movement or Brexit. Finally, the historical evolution of government has left the principle of separation of powers struggling to adapt to the complexity of modern governance. Designed for simpler political contexts in a bygone age, it often falters in addressing issues like economic crises, pandemics, and technological change, which demand centralised decision-making rather than deliberative separation.

In sum, while the separation of powers remains a cornerstone of liberal democratic theory, its practical application often falls short. The interplay of partisan politics, bureaucratic expansion, executive dominance, and globalisation has not merely diluted its effectiveness; it has completely undermined it. In the face of these challenges, modern democracies must grapple with how to balance the ideal of separated powers with the practical demands of governance in a complex and interconnected world.

Overlaps and intersections

Let’s represent the three branches of government as three overlapping circles in a Venn diagram. If there were true separation of powers, the intersections would be empty. In reality, the intersections are well populated. Each intersection represents a different way in which the separation of powers can be compromised:

• Executive + Judiciary: Political Justice
• Legislative + Executive: Legislative Deference
• Legislative + Judiciary: Judicial Legislation
• Executive + Legislative + Judiciary: Consolidated Authority

The history of twentieth-century politics in Europe and the United States provides all too many examples of how these overlaps have manifested in practice, often with profound consequences.

One way the separation of powers is undermined is through the relationship between the executive and judiciary, a dynamic that can result in “political justice.” This occurs when one branch influences the other, compromising the independence essential to both. For instance, the judiciary sometimes serves to legitimise executive actions, as seen in the landmark case of Korematsu v. United States (1944). Here, the U.S. Supreme Court upheld Executive Order 9066, which authorised the internment of Japanese-Americans during World War II. This ruling exemplifies how the judiciary can succumb to political pressure during times of crisis, validating actions that later come to be recognised as unconstitutional and discriminatory.

Conversely, judicial deference can occur when courts abandon impartiality in favour of executive authority, particularly under authoritarian regimes. In Nazi Germany, the People’s Court (1934–1945) became a tool of Hitler’s regime, issuing death sentences to political dissenters such as members of the White Rose resistance group. The judiciary’s role as an independent check on power was effectively obliterated, reducing it to an instrument of state terror.

On the other hand, judicial overreach represents the opposite extreme, where courts interfere with executive authority by blocking actions and straying into policy making. An example of this dynamic is the Youngstown Sheet & Tube Co. v. Sawyer (1952) case, where the U.S. Supreme Court struck down President Truman’s executive order to seize steel mills during the Korean War. While the decision was celebrated as a victory for checks and balances, critics argued that the judiciary overstepped its bounds, interfering in urgent executive wartime decisions.

The relationship between the legislature and executive also presents vulnerabilities to the separation of powers, often leading to what can be termed “legislative deference.” When these branches cooperate too closely, legislative independence may be eroded. One manifestation of this is policy capture, in which both the executive and legislature collaborate to serve private or partisan interests rather than the public good. A notable example of this is the lobbying surrounding the 1986 Tax Reform Act in the United States, where corporate interests significantly influenced the final legislation. By prioritising the demands of powerful economic stakeholders, both branches undermined their accountability to the broader electorate.

Rubber-stamping is another form of legislative deference, where legislatures unquestioningly approve executive proposals, often due to strong party discipline or coercion. This dynamic was starkly evident in Germany with the passage of the Enabling Act of 1933. By granting Adolf Hitler’s government the authority to enact laws without parliamentary approval, the Reichstag effectively surrendered its legislative power, paving the way for totalitarian rule.

On the other hand, legislative overreach occurs when legislatures attempt to control executive functions, such as micromanaging foreign policy or military operations. In the United States, the War Powers Resolution of 1973 exemplifies this tension. Intended to limit the president’s authority to deploy troops without congressional approval, the resolution has been criticised for intruding on the executive’s ability to manage military affairs effectively.

Another way the separation of powers can be undermined is through the overlap between the legislature and judiciary, a phenomenon often referred to as “judicial legislation.” This dynamic occurs when judicial decisions effectively dictate policy or when legislatures retaliate against perceived judicial encroachments. Judicial activism, where courts establish new legal norms that resemble legislative acts, exemplifies this overlap. In Brown v. Board of Education (1954), the U.S. Supreme Court declared racial segregation in public schools unconstitutional. This decision, while transformative and morally justified, effectively legislated social reform in the absence of congressional action on civil rights.

In contrast, legislative retaliation involves lawmakers curbing judicial independence, often in response to controversial rulings. The UK’s Constitutional Reform Act of 2005 illustrates this dynamic. Although not strictly a case of retaliation, the act restructured the relationship between the judiciary and Parliament by abolishing the House of Lords’ judicial role, a move seen by some as an attempt to reassert legislative control over an increasingly independent judiciary.

The most extreme breakdown of the separation of powers occurs when all three branches align, leading to what can be described as consolidated authority. This total erosion of checks and balances enables authoritarian rule or extreme partisanship. Authoritarian regimes are marked by the complete subjugation of the legislature and judiciary to the executive, as seen in Fascist Italy under Benito Mussolini from 1925 to 1943. In this system, laws were passed through a compliant legislature, enforced by subservient courts, and executed without constraint by Mussolini’s regime. The alignment of all branches under one leader effectively eliminated any possibility of accountability or resistance.

A less overt but similarly troubling phenomenon is partisan collusion, where extreme partisanship drives all branches to act in concert for party goals, disregarding institutional checks. During the Red Scare in the United States, the executive, legislative committees like the House Un-American Activities Committee (HUAC), and the judiciary worked together to suppress dissent, targeting alleged communists with little regard for due process or the separation of powers. This alignment, known as McCarthyism, illustrates how partisanship can undermine the independence of each branch, creating an environment of fear and repression.

The separation of powers, while essential to democratic governance, is continually vulnerable to erosion through these interactions and overlaps between branches of government. From judicial deference in Nazi Germany to the legislative rubber-stamping that enabled Hitler’s rise, history reveals the profound consequences of failing to maintain institutional independence. Whether through executive dominance, legislative acquiescence, judicial activism, or consolidated authority, the undermining of this principle highlights the ongoing need for vigilance in preserving the delicate balance that underpins constitutional governance.

The administrative state

Even when the various contingencies described in some of the examples above are not present, the very structure of the administrative state tends to blur the boundaries between the three branches of government. The rise of the administrative state in fact represents a profound structural challenge to the classical principle of the separation of powers. When the framers of the US Constitution drafted their vision of government 250 years ago, they sought to establish a system in which legislative, executive, and judicial functions were clearly delineated. This separation was intended to prevent tyranny and maintain accountability by ensuring that no single branch could dominate the others. However, the emergence of powerful administrative institutions has fundamentally altered this balance, blurring the distinctions between these branches and centralising authority in ways that Montesquieu, Madison, and their contemporaries could scarcely have envisioned. The administrative state — characterised by sprawling bureaucracies that wield legislative, executive, and judicial powers simultaneously — renders the classical model of the separation of powers even less realistic today than it was when the Constitution was conceived.

One way the administrative state undermines the separation of powers is through its rulemaking processes, which conflate legislative and executive functions. In the United States, agencies such as the Environmental Protection Agency (EPA) and the Securities and Exchange Commission (SEC) issue detailed regulations that carry the force of law. While these agencies derive their authority from broad enabling statutes passed by Congress, they effectively legislate by crafting rules that fill in the gaps left by vague or open-ended laws. This dynamic reflects a shift of legislative power into the executive branch, as unelected bureaucrats draft policies that directly affect citizens’ lives. Congress, meanwhile, often lacks the expertise or capacity to challenge these rules, resulting in weak oversight and a diminished role in detailed policy making.

This erosion of legislative authority is not unique to the United States. In the European Union, the European Commission — an executive body — drafts binding regulations and directives that member states are obligated to implement. National parliaments, rather than serving as primary lawmakers, are often relegated to the role of transposing these directives into domestic law with limited discretion. The concentration of rulemaking power in Brussels reflects a broader trend in which elected legislatures play second fiddle to unelected technocrats. In both the U.S. and Europe, the rise of administrative rulemaking has hollowed out the role of representative legislatures, undermining the principle that lawmaking should be the exclusive domain of elected officials.

The administrative state also blurs the line between executive and judicial functions by merging enforcement and adjudication within single institutions. In the United States, agencies such as the Federal Trade Commission (FTC) not only investigate and enforce violations of competition law but also adjudicate disputes in their own administrative courts. Administrative Law Judges (ALJs), who preside over these hearings, are technically part of the executive branch, raising serious concerns about impartiality. When an agency acts as both prosecutor and judge, it consolidates powers that were meant to remain separate, thereby undermining the judiciary’s independence.

Similar dynamics are evident in Europe. The European Central Bank (ECB), for instance, has the authority to enforce financial regulations and impose penalties, bypassing traditional court systems in many cases. National regulatory bodies across Europe often possess adjudicatory powers, handling disputes and appeals internally rather than deferring to independent judicial review. These arrangements weaken the judiciary’s role as a check on executive authority and create institutions that defy Montesquieu’s vision of distinct and independent branches of government.

Perhaps the most striking way the administrative state undermines the separation of powers is through the consolidation of authority into technocratic institutions. These institutions centralise legislative, executive, and judicial functions under the guise of expertise and efficiency, creating what some have called a “fourth branch of government.” In the United States, the Department of Health and Human Services (HHS) exemplifies this trend, overseeing vast welfare programs like Medicare and Medicaid while simultaneously creating policies, enforcing compliance, and resolving disputes. Similarly, in Europe, the European Commission wields executive, legislative, and quasi-judicial powers, making it one of the most powerful and centralised institutions in the EU. This concentration of authority reflects a departure from the classical model of governance, as administrative agencies transcend the traditional boundaries between branches of government.

The rise of the administrative state also has profound implications for the balance of power. Legislatures, overwhelmed by the complexity and technicality of modern governance, often defer to agencies that possess the expertise and resources to handle intricate policy matters. This deference allows agencies to take on quasi-legislative roles, further marginalising elected lawmakers. Judicial independence is similarly weakened by doctrines such as Chevron deference in the United States, which requires courts to uphold an agency’s interpretation of a statute unless it is deemed unreasonable. This principle not only empowers agencies to act as interpreters of their own authority but also reduces the judiciary’s ability to serve as an effective check. Meanwhile, administrative agencies, as part of the executive branch, expand the power of the presidency by centralising control over vast swaths of public policy.

These dynamics make the separation of powers less realistic today than it was 250 years ago. At the time of the Constitution’s drafting, the framers could not have foreseen the emergence of a complex administrative apparatus capable of consolidating legislative, executive, and judicial functions within itself. By creating institutions that blur the lines between branches of government, the administrative state challenges the very foundations of constitutional governance. Whether through rulemaking that sidelines legislatures, enforcement mechanisms that bypass independent courts, or the centralisation of authority in technocratic bodies, the rise of the administrative state represents a structural transformation that fundamentally undermines the classical concept of the separation of powers.

The impossible state

I’ll conclude this essay with a brief discussion of Wael Hallaq’s devastating critique of the intricate entanglement of the judiciary with the state apparatus in *The Impossible State* (2012), which poses a far reaching challenge to the liberal ideal of judicial independence. Hallaq demonstrates that judges, far from being impartial arbiters, are deeply embedded within the socioeconomic and political structures that define the modern state. By exploring how the judiciary functions as both a tool of the state and an entity constrained by the state’s legal and political framework, Hallaq critiques the very foundations of modern judicial practice, further undermining the whole idea of the separation of powers. His argument reveals how the judiciary serves not only as an interpreter of the law but also as a mechanism for reinforcing state power and legitimizing its authority.

Hallaq begins by situating judges within their broader social and political contexts, drawing on the insights of Ralph Miliband to argue that judicial independence is illusory. Judges are shaped by factors such as class, education, and professional associations, which align them with the dominant interests of the state. This alignment is further reinforced by the judiciary’s inherently conservative nature, which prioritises the preservation of state interests and the status quo. Hallaq points out that the judiciary is structurally bound to uphold the state’s conception of privilege, capital, and property, effectively serving the interests of elites. Even the educational systems that train judges are deeply intertwined with state ideology, producing judges who are predisposed to align with the state’s priorities. Thus, the judiciary cannot escape its dependence on the state, as it is both a product of the state’s apparatus and an instrument of its governance.

While the judiciary may occasionally address the grievances of the underprivileged, Hallaq argues that its ability to do so is limited by the predetermined boundaries of the legal framework. Judges are bound by laws that they must apply, even when those laws are harsh or oppressive. In enforcing these laws, judges legitimise the state’s authority, reinforcing its dominance even in moments of apparent dissent. Hallaq acknowledges that some judges may exercise discretion to mitigate the effects of unjust laws or resign in protest, but these instances are rare exceptions to the norm. On average, judges have historically demonstrated a willingness to strengthen the state’s hand, particularly in its encounters with dissent. This structural dynamic, Hallaq suggests, ensures that the judiciary functions as an extension of the state’s power, rather than as an independent check on it.

The judiciary’s embeddedness within the state system also has profound implications for its relationship with the executive. Hallaq critiques the whole theory of a strict separation of powers, arguing that such a separation is impossible in practice. Judges do not merely interpret and apply general legal norms; they also perform executive functions by establishing delicts and ordering sanctions. In doing so, the judiciary becomes an executor of the state’s legal and political will, blurring the lines between judicial and executive authority. This dual role underscores the judiciary’s role as an instrument of state governance, further eroding the ideal of judicial independence.

Through this critique, Hallaq exposes the judiciary as a central mechanism through which the modern state consolidates and legitimizes its power. The judiciary’s structural and functional dependence on the state ensures that it serves the state’s interests, reinforcing the dominance of elites and maintaining the state’s authority over its citizens. By highlighting the judiciary’s role in legitimising oppressive laws and strengthening state power, Hallaq challenges the liberal conception of the judiciary as an impartial arbiter of justice. His argument calls into question the very foundations of the modern state’s legal and political order, inviting readers to reconsider the possibilities of justice beyond the constraints of the modern judiciary.

Given all these criticisms, most of which are well known to legal scholars and political scientists, one is left wondering why anyone takes the separation of powers at all seriously any more. Hallaq’s analysis in particular exposes the concept as little more than a convenient fiction, masking the reality of a judiciary that is inextricably bound to the state’s structures and interests. Far from acting as an independent check on power, the judiciary legitimises and enforces state authority, often at the expense of justice and dissent. This calls into question not only the viability of the separation of powers but also the broader ideological foundations of modern legal and political systems, which require a radical reimagining if we are to move beyond their fatal flaws.