Introduction
The separation of powers is a doctrine concerning the division of governmental authority among different branches to prevent the concentration of power and promote a balanced state. The technical principles of this doctrine involve distributing legislative, executive, and judicial functions to distinct institutions, each with specific responsibilities and limitations. The key requirement for an effective separation of powers is that each branch operates independently, with checks and balances to prevent any one branch from dominating the others. This structure promotes accountability and protects against potential abuses of power.
The Legislative Branch: Parliament
In the UK, the legislative function primarily rests with Parliament, comprising the House of Commons and the House of Lords. Parliament's core responsibility is creating, amending, and repealing primary legislation. This process involves debating bills, scrutinizing government proposals, and ultimately voting to enact laws. The legislative process ensures that laws are created through a democratic procedure with input from elected representatives and a degree of oversight from the unelected upper chamber. Parliamentary sovereignty, a central tenet of the UK constitution, dictates that Parliament possesses the ultimate legal authority to make laws, which are not subject to review by any higher body, within the UK. For instance, the Parliament Acts of 1911 and 1949 established the legislative supremacy of the House of Commons. However, this has been significantly impacted by EU law and the HRA 1998.
Secondary Legislation and Delegated Powers
While Parliament is the primary lawmaker, it also delegates legislative power to the executive through enabling statutes. This delegated legislation, often referred to as secondary legislation or statutory instruments, allows government ministers or other bodies to enact detailed rules and regulations within the scope of a statute. While this process can enhance efficiency and administrative expediency, it also necessitates the inclusion of oversight mechanisms to prevent unchecked power being wielded by the executive. Consequently, this is subject to judicial review.
The Executive Branch: Government
The executive function is primarily exercised by the Government, led by the Prime Minister, and includes government ministers and civil servants. The Government’s primary duty is to administer the state by formulating and implementing public policies, managing day-to-day affairs, and overseeing various governmental agencies. As outlined in CCSU v Minister for the Civil Service [1985], the executive also exercises power via prerogative powers, a residue of royal powers. Examples include the power to enter into treaties, appoint ministers, and deploy armed forces.
Prerogative Powers and Accountability
While the executive exercises a variety of prerogative powers, these are not absolute, and have been recognised as subject to judicial review, as confirmed in R (Miller) v Prime Minister [2019]. This check is particularly important, as demonstrated in Attorney-General v De Keyser’s Royal Hotel [1920], where the court ruled that the Crown could not rely on prerogative powers to circumvent established statutory provisions. This demonstrates a clear principle that where Parliament legislates on a matter which has also been addressed by prerogative powers, the statute takes primacy over the prerogative, a limitation imposed on the executive by virtue of Parliament's will and the judiciary's interpretation of law.
The Judicial Branch: The Courts
The judicial branch, headed by the Supreme Court, interprets and applies the law, resolving disputes and ensuring that the other branches of government act lawfully. The courts also hold the executive and legislature accountable, as demonstrated by R (Anderson) v Secretary of State for the Home Department [2002]. Here, the House of Lords held that the Secretary of State's power to set tariffs for mandatory life sentences was incompatible with Article 6 of the ECHR, further highlighting judicial oversight to ensure compliance with human rights legislation. In addition, the case demonstrates the courts' approach to s3 of the Human Rights Act, where they ruled that the legislation could not be interpreted in a way that would fundamentally alter the intent of the statute.
Judicial Review and its Limits
The courts have the power to conduct judicial review of executive and legislative actions to ensure they comply with legal and constitutional principles. In CCSU v Minister for the Civil Service [1985], the courts affirmed that the royal prerogative is subject to judicial review, with the court establishing three grounds for challenging executive action: illegality, irrationality, and procedural impropriety. However, there are limits to the courts' powers, as they can only rule on the legality of actions and not their political merit. Cases such as R (Lord Carlile) v Home Secretary [2014] showcase that the courts will defer to executive judgment on matters of national security and foreign policy, unless an error in law is established.
Checks and Balances
The UK system employs various checks and balances, which create overlap, to ensure that no one branch of government becomes too powerful. The executive is responsible to Parliament, through scrutiny, questions and oversight, where its ministers must regularly answer for their actions. The judiciary can also check executive action through judicial review and the legislative actions of parliament by declaring incompatibilities with the ECHR under the Human Rights Act 1998, with an obligation to take the European Court of Human Rights jurisprudence into account.
Parliamentary Sovereignty and its Constraints
While parliamentary sovereignty is a central concept, as illustrated in Pickin v British Railways Board [1974], where the House of Lords held that the courts cannot question Parliament's proceedings, this is no longer absolute. EU law, prior to withdrawal, and the HRA 1998, have placed further constraints upon the sovereignty of Parliament. Although Parliament can repeal either, by virtue of enacting the original legislation, it could potentially be argued that this has always been the case and it cannot be said that Parliament has relinquished its sovereignty. The recent Brexit debate demonstrates that Parliament can exercise its powers even when it is not in agreement with the executive, further highlighting the tensions created by the separation of powers.
Case Studies Illustrating Separation of Powers
Several landmark cases demonstrate the practical application of the separation of powers in the UK. Entick v Carrington (1765), while not explicitly about separation of powers, established that the Crown could not arbitrarily enter private homes or seize property without the authority of law. This landmark case is often cited as an early example of the judiciary limiting executive power.
In R v Secretary of State for the Home Department, ex parte Fire Brigades Union [1995], the House of Lords ruled that the Home Secretary acted unlawfully by seeking to use prerogative powers to circumvent an Act of Parliament. The court clarified that once Parliament has legislated on an issue, the executive can no longer use prerogative powers to undermine Parliament’s intention. R (Miller) v Prime Minister [2019], commonly referred to as Miller II, ruled that the Prime Minister's prorogation of Parliament was unlawful, because it frustrated Parliament's constitutional function, reinforcing that the executive cannot prevent scrutiny from Parliament. In addition, the ruling clarified the limits on prerogative powers and judicial authority to review their exercise.
R (on the application of Miller) v Secretary of State for Exiting the European Union [2017], commonly referred to as Miller I, determined that the executive required a vote in parliament before triggering Article 50 of the Lisbon Treaty, demonstrating that Parliament has to authorise any fundamental constitutional change. This was a critical case highlighting the legislative supremacy of Parliament and the limitations that EU law imposed upon the authority of the executive, and also the supremacy of Parliament through common law by using case law to provide the parameters of statutory interpretation.
In relation to the role of the judiciary in determining whether to give effect to legislation, R v Chaytor and others [2010] concluded that Parliamentary privilege does not extend to a criminal investigation regarding MP’s expenses claims. This has implications for the relationship between the legislature and judiciary as the case determined the extent of Parliamentary privilege.
The case of R (Gentle) v Prime Minister [2008] concluded that although Article 2 of the ECHR does not place a duty on the government to ensure that armed forces are not sent to unlawful wars, it does however, allow the courts to examine the actions of government through judicial review. This is consistent with earlier precedent and demonstrates that limitations on executive power and accountability, as a principle, are maintained.
The importance of adhering to the principle of natural justice was further highlighted in R v Foreign Secretary, ex parte Bancoult (No 2) [2008], which clarified that the exercise of prerogative power is subject to judicial review and may be deemed unlawful. It further illustrated that the exercise of the prerogative must not be an abuse of power.
Finally, R (Quila) v Secretary of State for the Home Department [2011] confirmed that the Immigration Rules infringed Article 8 ECHR by preventing the entry of spouses under 21. The case clarified that when using discretionary powers, it is necessary for the decision-maker to act proportionately, in order to uphold human rights.
Conclusion
The separation of powers in the UK is a complex and dynamic principle. While the UK does not have a codified constitution which clearly defines the separations, the framework operates through various legal mechanisms, conventions, and historical precedents that are subject to constant judicial interpretation, as demonstrated by R (Miller) v Prime Minister [2019]. Through the operation of checks and balances, each branch is constrained by the other, providing a balance of power and, ultimately, an effective government. These include the role of Parliament in creating legislation, the role of the Executive in implementing and administering policy, and the role of the Judiciary in ensuring both the Legislature and the Executive do not act in excess of the legal parameters defined by the separation of powers doctrine. By analysing these specific areas, one can see the influence that case law and legislation have upon the separation of powers doctrine as a whole and how these various aspects interact with each other.
