Define: Separation Of Powers

Separation of powers is a fundamental principle in democratic governance that divides the functions of government among separate branches – typically, the executive, legislative, and judicial branches – to prevent any one branch from gaining too much power. Each branch has distinct responsibilities, functions, and powers, and they operate independently of one another, providing a system of checks and balances. This system aims to ensure accountability, prevent abuses of power, and safeguard individual liberties by requiring cooperation and negotiation among the branches to enact laws, execute policies, and adjudicate disputes. Separation of powers is a cornerstone of constitutional democracies worldwide, promoting stability, fairness, and the rule of law.

It is widely accepted that for a political system to be stable, the holders of power need to be balanced against each other. One of the reasons widely cited is that it leads to a more just and humane system of government. This need not invariably be the case, but, as Lord Acton said, power tends to corrupt, and absolute power corrupts absolutely. By maintaining a balance between political forces, power is prevented from being concentrated in the hands of people who would be tempted to abuse it. But, in fact, we see this separation of powers not only in just and humane societies but in oppressive ones as well. Its real, practical benefit is the stability it engenders. While a stable system may be oppressive and unpredictable, experience has shown that it is far less likely to exhibit these characteristics than an unstable one.

Although not famed for his views on constitutional law, Terry Pratchett summed up the driving force behind the separation of powers very succinctly in one of his novels. People say they want freedom and equality, as one of his characters opines, but what they really want is for tomorrow to be the same as today. In other words, what society needs is continuity and predictability in government.

The concept of separation of powers is not a new one, nor is it confined in its operation to modern democracies. Even the notion that the most efficient separation is into three distinct bodies rather than some other number is an ancient one. The Greek philosopher Aristotle wrote that the fairest political system would be one in which power was shared between the monarchy, the aristocracy, and the common people. In the 17th century, John Locke put forward a more modern proposition: that government should be divided between an executive and a legislature. The role of the executive would be to implement the law and administer the country, while the legislature would create and manage the law itself. The problem with Locke’s system is that there is nothing to prevent one arm of the government from overwhelming the other. Our modern notions of separation of powers are, in fact, mostly derived from the writings of 18th-century French political theorist Charles de Montesquieu. Ironically, his concepts of an ideal political system were drawn, at least in part, from his observations of England. In reality, the separation of powers he describes has never been fully implemented in England or, quite likely, anywhere else. However, at the time of Montesquieu, England had just had a civil war and deposed a despotic monarch in favour of a representative democracy and courts with constituted and well-defined powers. In France, in contrast, Monarchs still enjoyed more or less unlimited power. In his book, The Spirit of the Law Montesquieu describes a system where power is balanced between an executive, a legislature, and a judiciary. The balance is a complex one. According to Montesquieu’s theory, the judiciary controls how the executive implements the legislation that the legislature has created. The judiciary would be limited by the legislature, as only the legislature would be empowered to create new law. The legislature could create laws but had no direct power to apply them. In the UK, the role of the executive is largely assigned to the ministers of the government and perhaps to the civil service and the police. Parliament as a whole forms the legislature, while the role of the judiciary is taken by the courts and perhaps to a certain extent by tribunals.

Montesquieu’s theories had a lot of influence, in particular in the nascent USA. His model of separation of powers is still the one against which others are judged. However, although his model was said to be based on the English constitution, closer inspection reveals that there are serious discrepancies between Montesquieu’s theory and political reality in the UK.

Perhaps the most striking anomaly is the dominance of the legislature over the executive. The leader of whichever party in the Commons can secure a majority forms the government (executive), according to long-standing custom. As a result, the executive is able to exert considerable pressure on the legislature. The rise of the party system in Parliament has made this situation worse. While the government is numerically only a small proportion of the total number of MPs, party loyalties encourage members of the government’s party to back it, even when their consciences and their constituents prefer otherwise. So, although legislation is the responsibility of Parliament, in reality, the legislative programme is driven by the government of the day. This, in itself, is not objectionable, so long as there is proper scrutiny and control of the government’s legislative programme by the legislature. When the government’s party has a large majority in the Commons, as is the case at present, there is almost no opportunity for Parliament to regulate the passage of legislation.

If the involvement of Parliament in the production of primary legislation has been truncated, it’s involvement in secondary legislation is now almost non-existent. In practice, the exigencies of administration dictate that a certain amount of delegated legislation is required, simply because the time pressure on Parliament is so great. However, some delegated powers are extensive. The so-called “skeleton “acts,” which merely give ministers a set of powers to exercise without containing any substantive law, are of particular concern. There are also worrisome ‘Henry VIII’ clauses in some Acts that grant powers to ministers to modify primary legislation. While these powers may improve the efficiency of the parliamentary process, they strengthen the executive at the expense of the legislature.

This situation results from the fact that in the UK, although formally the purpose of general elections is to elect parliamentary representatives, the party system means that, in fact, we are electing the government. In some countries, elections are held separately for the legislature and the executive; in the UK, these roles are essentially fused.

The situation isn’t entirely hopeless. It is not a forgone conclusion that the government will be able to introduce the legislation it desires in the form that it wishes. Governments are sometimes defeated by their own backbenchers or by the House of Lords. However, where the government really wants to introduce a fundamental piece of legislation, it can make it an issue of confidence. The threat that the government may have to resign and thus bring about a dissolution of Parliament is usually enough to get even the most recalcitrant backbencher to toe the line.

There are further problems with the separation of powers between the executive and the judiciary, although these are less troublesome in practice than they have the potential to be. Surprisingly, the appointment of the judiciary is entirely in the hands of the executive. The head of the judiciary, the Lord Chancellor, is a Cabinet minister selected by the Prime Minister. The Lord Chancellor either appoints or advises on the appointment of all other judges (notionally, the sovereign is responsible for the appointment of judges, but in practice, this is a formality). However, senior judges, once appointed, cannot be removed from office at the whim of the executive, unlike the Lord Chancellor himself, so there is a measure of independence after appointment. Nevertheless, the current Lord Chancellor has attracted criticism for what has been seen as an attempt to ‘politicise’ the judiciary by inviting senior lawyers (potential candidates for judicial office) to contribute to party fund-raising activities.

In fact, the office of Lord Chancellor is itself an anomalous one, involving elements of judicial, executive, and legislative responsibility. There have been calls for the Lord Chancellor to remove his office from direct involvement in the selection of judges. Recently, an independent appointments commission was set up to scrutinise the selection process, although it does not have any direct influence. The recent creation of a Select Committee on the Lord Chancellor’s Department has opened up the Lord Chancellor’s role to a higher level of Parliamentary scrutiny, and the current Lord Chancellor has let it be known that reform of his role is not entirely ruled out. So we may see changes here in the future.

The judiciary can, and does, hold the activities of the executive up to scrutiny, often through the process of judicial review. It is now accepted that, where an Act of Parliament gives a minister or other administrator discretion, that discretion must be exercised according to law, rationally, and in accordance with the principles of natural justice. The passage of the Human Rights Act has further strengthened the position of the judiciary. It provides the opportunity to quash an administrative action on human rights grounds and may have added a test of ‘proportionality’ to the grounds for judicial review (see, for example, R.Daly v. Secretary of State for the Home Department (2001)). Often, the involvement of the courts in the activities of ministers is seen as a hindrance by the government. Occasionally, legislation attempts to oust the jurisdiction of the courts to review the exercise of ministerial discretion. Even where this ousting is strongly worded and uncompromising, the courts have often been ingenious in finding ways to circumvent it (see, for example, Ansiminic v. Foreign Compensation Commission (1969)).

And so we come on to the separation of powers between the judiciary and Parliament. In reality, we have more of a sharing of powers than a separation. Montesquieu believed that judges should not be legislators, but there is now little doubt that in our common-law system, judges do have a legislative role. The judges themselves are not keen to acknowledge this and often go to some lengths to disguise it. However, while there are certain influential judges who openly and firmly refute the idea that judges create law, the senior judiciary is increasingly coming clean about it. The fact that judges may have what is essentially a legislative role is discomforting since we have grown used to the idea that the legislature is a body of our elected representatives, for all its faults. The judges are not only not elected; coming from a narrow social and political band, they are not even representative.

Despite the overlap between the judiciary and Parliament in legislation, the order of precedence is clear. Since the 17th century, the courts have deferred to the authority of Parliament. It is generally accepted that the courts are not empowered to rule on the validity of acts of Parliament. Interestingly, the balance of power may have shifted somewhat with our increased obligations to Europe. In the Factortame Sage (1990–present), we saw that the courts could disapply even primary legislation where it was in conflict with our treaty obligations to Europe as defined by the European Communities Act (1972). Similarly, the Human Rights Act has given courts the power to issue a declaration that primary legislation is incompatible with the European Convention on Human Rights.

So, we can see that there are tensions between the goals, motives, and procedures of the executive, legislature, and judicial arms of government, and this is all for the good. Separation of powers requires that these bodies remain in a state of dynamic interplay, with no one body being able to dominate the others. At the same time, there are places where the powers that Montesquieu thought should be separated are, in fact, fused. All three arms of government exercise functions that, in a strict separation of powers, should really reside elsewhere. The executive exercises legislative powers by dominating Parliament. It exercises judicial responsibilities whenever an administrator exercises discretion to decide in favour of, say, one planning application rather than another. The judiciary creates law, albeit subtly and with circumspection. Parliament is able to discipline and hold its members to account without the involvement of the courts. And so on.

It should be clear that our system of government is a long way from Montesquieu’s ideal. What is most surprising, however, is that it works as well as it does. Ultimately, I believe, it is the acceptance of constitutional conventions that keeps things ticking over. The government could, for example, further dominate Parliament by controlling the timetable for the consideration of legislation, but, on the whole, it does not. Parliament could legally enact legislation that transfers the power to decide disputes away from the courts and more to administrators, but it does not. Judges could make radical changes to the law rather than incremental ones, but, on the whole, they don’t. And so on. We don’t have a codified written constitution that sets out the balance and separation of powers, so, ultimately, it is convention that controls these things. And conventions work because everyone wants tomorrow to be the same as today.

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This glossary post was last updated: 9th April, 2024.