Tagged as: UK Law

Constitutional Institutions Lecture

The Separation of Powers

Public law regulates the relationship between the state and its organs, and private citizens. Public law is a shorter way of describing constitutional and administrative law. Constitutional law is the law that provides a state framework and establishes its principle institutions and the interrelationships between these institutions. Administrative law confers the legal powers and legal duties of public bodies and authorities.

The separation of powers serves an essential democratic function, since it enables the three main powers of the state to act as a check on the absolute exercise of power. These powers are divided between three principle branches of government. Firstly, the legislative branch has powers to create legislation and to represent the views of the people. Second, the judicial branch is the systems of courts and tribunals who have powers to interpret legislation passed by the legislature and to adjudicate on legal disputes. Thirdly, the executive branch has the responsibility of making and implementing public policy.

Throughout history, many constitutional writers have regarded the separation of powers principle as representing the ideal structure of government. Charles Louis de Secondat, otherwise known as Baron de Montesquieu wrote about his observations whilst travelling around Europe between 1728 and 1731. He is one of the writers who is most closely associated with this doctrine. In The Spirit of Laws, Montesquieu warned against the use of power in a 'tyrannical manner' if it was not divided between the three branches of government. Much of his observations were carried out within the court of George II in England, moving in political circles and formulating much of his work based on the English government of the time.

Modern democracies tend to now exist as a partial, or 'checks and balances', conception of the separation of powers, which includes the ability of one branch to involve itself in issues that are primarily the concern of another branch. Constructive breaches of the strict separation of powers doctrine can contribute to the overall goal of preventing tyranny; whereas destructive breaches pose a threat to that goal. Many states with constitutions based upon the tripartite system have experienced the development of many administrative organs that carry out many of the daily tasks of government. These agencies do not fit easily into any of the three branches.

The UK possesses governmental bodies, some of which are headed by government Ministers, which do not fit exclusively into either the executive, judiciary or legislature. Although very few countries adhere rigidly to the separation of powers doctrine, most constitutional systems do attempt some form of demarcation between the legislature, executive and judicial organs of government to avoid abuse of power by any one of the three branches.

Separation of Powers and the Constitution

The exact position of the doctrine of the separation of powers within the UK constitution is unclear. There are various different views as to whether the doctrine is part of the UK constitution. In Hinds v The Queen [1977] AC 195, Lord Diplock stated that he was certain that

'the basic concept of the separation of legislative, executive and judicial power...had been developed in the unwritten constitution of the United Kingdom'(at 212).

In The English Constitution (London, 1867) Bagehot argues that the

"efficient secret of the English Constitution may be described by the close union, the nearly complete fusion, of the executive and legislative powers".

There is a significant overlap in the work of the executive and the legislative branches, with the executive exerting a substantial influence over the work of Parliament. This creates a threat to the ability of the separation of powers doctrine to effectively prevent the abuse of power in the UK. At the same time, there are examples where separation of powers is strictly adhered to, such as in relation to the independence of the judiciary. Opinions vary on how best to achieve the balance between the separation of government institutions and the need for those institutions to work together and cooperate. There is no single answer to achieving the right balance.

In R v Secretary of State for the Home Department, ex p Fire Brigades Union [1995] 2 AC 513 the Home Secretary was unwilling to invoke powers under s 171(1) Criminal Justice Act 1988 which introduced a new scheme to offer compensation to victims of criminal offences. Since the Home Secretary was refusing to put into effect powers vested in him by the legislature, the case raised the question as to whether such a refusal was in accordance with the doctrine of the separation of powers. The Home Secretary was in effect repealing an Act of Parliament, which was not within his power to do so.

A three-fifths majority of the House of Lords held that the Home Secretary had exceeded his powers. The majority found that he had acted unlawfully by ruling out the possibility of the implementation of the statutory compensation scheme. The minority judgment held that since the legislation was not yet in full force, it was inappropriate for the court to intervene, making the issue a political one. Judicial intervention in their view would involve a breach by the judiciary of the separation of powers doctrine. The case illustrates how a different emphasis on one particular aspect of the separation of powers can lead to a different conclusion. The majority emphasised the importance of the executive not overreaching its powers, whereas the minority considered the non-interference of the judiciary in areas beyond its concern as the overriding factor.

The important aspect regarding the separation of powers doctrine, thus, is less in its specific formulation, but in its ability to prevent the abuse of power of any one of the three branches of government. Although appearing simplistic, complexity is introduced when various parts of the doctrine are interpreted as taking precedence over others and the need to balance the doctrines checks on abuse of powers with the need for branches to co-exist in relationship with one another. The three branches of government will now be examined in further detail.

Example Exam Question

Assess the importance or otherwise of the doctrine of separation of powers in relation to the constitution of the United Kingdom

The Institutions - the Executive

The executive branch of the UK government is comprised of the Head of State, or monarch, the Prime Minister, the Cabinet, Secretaries of State, ministers of the Crown, departments of state, other public bodies, devolved administrative bodies, local authorities, the police and the military.

The Prime Minister is appointed by the Head of State; if appointed after a General Election, this takes place soon after the outcome is announced. The formal process involves the outgoing Prime Minister tendering his or her resignation to the monarch, and then his or her successor is requested by the Head of State to form a new government.

The powers of the executive

Primarily the executive has a vast array of statutory powers afforded to it by Parliament. Since Parliament is unable to legislate for every eventuality, the Inquiries Act 2005 makes provision for inquiries into matters of public concern, so that every time something of public concern occurs, Ministers have the power to set up an inquiry within specific parameters, instead of Parliament having to legislate each time to deal with the specific incident.

The Prime Minister's powers come from the Royal Prerogative and statute. He or she has a role to advice the monarch on:

  • the exercise of all powers of entitlement which concern the government;
  • the appointment of all members of the judiciary, heads of the security services and senior officers in the Church of England.

The Prime Minister also appoints senior officers in the armed forces, and recommends honours or life peerages. The Prime Minister also makes decisions regarding the Cabinet, such as determining its size, controlling its agenda and creating and disbanding Cabinet Committees.

The Cabinet is chosen by the Prime Minister and appointed by the monarch. It is made up of around 20 members, but this number varies. The Cabinet functions to consider questions which concern the collective responsibility of government and are of critical importance to the public. The Cabinet determines the contents of the Queen's speech, the legislative timetable and the broad economic policy, which establishes the basis of the Chancellor of the Exchequers budget.

Standing and ad hoc Cabinet Committees are empowered by the Cabinet to deal with matters of current importance. The Cabinet have a relationship with the monarch, who is represented by the Prime Minister in Cabinet meetings and is entitled to be informed before being required to grant approval for documents sent by the Prime Minister.

In AG v Jonathan Cape [1976] QB 752, [1976] 3 All E R 484 Lord Widgery CJ described 'collective cabinet responsibility' as meaning that any policy decision reached by the Cabinet had to be supported by all members of the Cabinet, unless they were willing to resign.

The Civil Service is required to act in a way that is independent of any political party; the employees will work for whichever political party is in government at the given time. The advantage of a politically neutral civil service, as laid down for in the Northcote-Trevelyan, Report on the Organisation of the Permanent Civil Service (House of Commons, 1854), is that it provides an element of stability despite political change in Parliament. The Constitutional Reform and Governance Act 2010 provides the statutory basis for the management of the civil service; it aims to address claims that the civil service had become less independent and closed to the political service of the government.

Examination Consideration

Note how the Royal Prerogative, is delegated through members of the executive through the relationship between the monarch and the Cabinet.


Devolution in the UK means that executive powers have been conferred upon executive organisations within Scotland, Wales and Northern Ireland.

The Scottish Government was established by part II Scotland Act 1998; it consists of the First Minister, the Scottish Ministers and the Scottish Law Officers. The First Minister is a member of the Scottish Parliament, nominated by its members and appointed by the monarch. The Scottish Ministers and the Scottish Law Officers are appointed by the First Minister and approved by the Scottish Parliament. A referendum held in Scotland in 2014, on independence from the UK, resulted in a 'No' Vote.

The Government of Wales Act 1998 (sections 52-55) established the Welsh Assembly. The Welsh Assembly is empowered to elect a First Secretary, who is subsequently empowered to appoint Assembly Secretaries. Committees and sub-committees may also be formed including the Welsh Administration Ombudsman, the Welsh Development Agency, the Development Board for Rural Wales, the Land Authority for Wales, and Housing for Wales.

The Government of Wales Act 2006 establishes the Welsh Assembly Government, which is separate from the Welsh Assembly. It deals with the appointment and remuneration of the First Minister and other Ministers, creates the office of Counsel-General to the Welsh Assembly Government, and makes provision for appointments and civil service staff.

The Secretary of State for Northern Ireland is the head of the executive in Northern Ireland. Executive powers are exercised by the Northern Ireland Executive, whose members are appointed by the Secretary of State. The Northern Ireland Act 2000 suspended the Northern Ireland Assembly, but this was re-established by the Northern Ireland Act 2006, along with a Northern Ireland First Minster and other Ministers.

Local Government

Local Government in England consists of areas of counties, districts, and unitary authorities created by the Local Government Act 1972, as amended in 1985 and 1992. Greater London and the Metropolitan Police District were established by the London Government Act 1963, the Local Government Act 1985, the Police Act 1996, and the Greater London Local Authority Act 1999.

In Wales, the Local Government (Wales) Act 1974 established twenty-two Unitary Authorities in Wales.

Scotland in made up of twenty-nine Unitary Authorities and three Island Authorities, according to the Local Government (Scotland) Act 1974.

Northern Ireland consists of the parliamentary counties of Antrim, Armagh, Down, Fermanagh, Londonderry and Tyrone and the parliamentary boroughs of Belfast and Londonderry. This is provided for in section 43(2) Northern Ireland Constitution Act 1973.

The Police

The police forces in the UK are part of the executive. The Police Act 1996 and the Police Reform Act 2002contain provision for the organisation of the police forces and police areas in England and Wales. Police Authorities have been established to secure the maintenance of an efficient and competent police force for the region. Police authorities make a plan outlining its objectives on an annual basis.

The Institutions - Parliament (Legislature)

Parliament is the institution that is responsible for the creation of new legislation, the scrutiny of bills and of holding the executive to account. The UK Parliament is located in Westminster in London and is comprised of the House of Commons (or lower house) and the House of Lords (the upper chamber). Local voters in general elections elect members of Parliament within the lower house. Finally, the monarch is formally the head of Parliament, and is required to give royal assent to legislation.

House of Commons

Member of the House of Commons are elected directly by UK citizens. Elections must be held at least once every five years; however, the governing Prime Minister has had the discretion to ask the monarch to dissolve Parliament in order that a general election is held at the most beneficial time for his or her political party. The Fixed-term Parliaments Act 2011 changed this rule to remove this discretion and provide that elections can only be called mid-cycle if there is a vote of no-confidence in the current government and no alternative government can be formed, or if two thirds (or more) of members of Parliament (MPs) agree to an earlier general election. A sunset clause provides that these terms in the Act are up for renewal in 2020.

The House of Commons as the representative assembly has come under criticism for its ability to represent the will of the people in the UK, in that:

  1. The current system of elections does not represent all parties equally within Parliament
  2. The House of Lords is unelected, however, it plays an important role in the making of the countries laws;
  3. There are insufficient women and ethnic minority MPs to represent the electorate.

There is no particular consensus on how MPs should represent their constituents. There is no agreement in political opinion as to whether the MP should attempt to represent the wishes of the majority of their constituents or that the constituents hand over power to their MP to use their own judgment to vote in the way they feel is most appropriate.

House of Lords

The second and upper chamber is the House of Lords, whose members are peers. The vast majority of peers are life peers who are appointed to the chamber and remain members for their lifetime. This is provided for in the Life Peerages Act 1958, which also permitted women to sit in the House of Lords. The House of Lords also retains ninety-two hereditary peers, who have inherited their title. The number of hereditary peers reduced signification due to the passage of the House of Lords Act 1999; the current hereditary peers will remain as members of the Lords for their lifetime. Reforms to the House of Lords by the 1997 Labour government led to a significant reduction of the number of hereditary peers who used to significantly outnumber the life peers and were unelected and mainly Conservative party members. Twenty-six bishops and archbishops (referred to as Lords Spiritual) of the Church of England are also members of the House of Lords until they retire from the roles in the Church.

The democratic legitimacy of the House of Lords has been drawn into question since they are not an elected body through the system of universal suffrage and cannot be removed by the electorate, since their role in the House of Lords is through appointment or inheritance. The House of Lords is going through a long-term period of reform, and a number of proposals have been made to improve its democratic legitimacy.

Examination Consideration

The judicial House of Lords and the parliamentary House or Lords must be distinguished. The judicial House of Lords was previously the highest appeal court in the UK, which has now been replaced by the Supreme Court. The parliamentary House of Lords is a part of the legislature and is still in existence, although is going through a process of reform.

Functions of Parliament

The House of Commons Select Committee on Procedure (First Report, 1987) concluded that there were four main areas of Parliamentary responsibility. These include enacting legislation, scrutinising the executive, controlling public spending and address the concerns of their constituents. Parliament's legislative role is the enactment of primary and secondary legislation, which is said to respond to social, economic and political changes in society, which require new laws to be made.

The House of Lords and the House of Commons perform distinct functions in relation to the creation of legislation. This is known as a bicameral system with two chambers that perform different functions. The House of Lords acts as a check on the abuse of power by the executive, by blocking legislation that the House of Commons have proposed. The House of Lords may delay legislation; however, under the Parliaments Acts of 1911 and 1949, it cannot be prevented if the House of Commons agree that it should be passed.

The Institutions - The Judiciary

The primary role of the Judiciary is to adjudicate on legal disputes that are brought before courts and tribunals in the UK. The primary sources of law in the UK are legislation or Acts of Parliament and the common law. The judges' role is in the interpretation of legislation and in the development of the common law. Judicial independence is of primary importance, it has implications for its relationship with the executive and Parliament, and provides public confidence in the judge's ability to adjudicate on disputes in an impartial manner. 

At first instance, the court must decide the case on the facts, make a determination of the relevant law and then apply the law to the facts that are found. This is the case for civil, criminal cases in courts and tribunals as well as judicial review proceedings. Facts are determined by the provision of evidence, often through witness statements or medical evidence.  A determination of the law can be a complex issue, the case may raise points of law relating to new statutory authorities, which have not been evaluated before. These cases may end up in the appeal courts if the parties feel that a mistake has been made regarding statutory interpretation. An application of the facts to the law in a criminal case for example requires a jury or magistrate to determine whether the essential legal elements of that particular offence are present within the factual scenario as determined by the evidence presented.

Judicial Review

One of the primary roles of the court systems is in holding the executive to account, by introducing accountability for the performance of public functions. This involves the checking, controlling and regulating of those functions. The Criminal Justice and Courts Act 2015, combined with cuts in legal aid, have made it harder to bring a case for judicial review, and hence presented the risk that government accountability has been undermined. 

The Senior Court Act 1981 and the Civil Procedure Rules are the most important legal instruments governing judicial review. In order to bring a claim for judicial review, claimants must illustrate at least one ground for judicial review is satisfied, or that a public authority has acted in a way that is incompatible with a human right included within the European Convention on Human Rights and Fundamental Freedoms 1950 (ECHR).

In Council of Civil Service Unions v Minister for the Civil Service [1985] AC 374, Lord Diplock outlined the three grounds upon which administrative action can be challenged via judicial review:

  • Illegality
  • irrationality
  • procedural impropriety

The role of Lord Chancellor is where the judiciary is said to meet the executive, prior to April 2006 the Lord Chancellor was head of the judiciary and had the power to appoint judges. The Lord Chancellor is a Cabinet minister; s.3 Constitutional Reform Act 2005 for the first time places a legal duty on government ministers to uphold the independence of the judiciary. The Ministry of Justice was created on 9 May 2007 and is responsible for courts, prisons, probation and constitutional affairs.

The Human Rights Act

The Human Rights Act 1998 (HRA) gives effect to the ECHR in UK law.

  • When interpreting the Convention section 2HRA, a UK court must take into account any judgement, decision or declaration or advisory opinion of the European Court on Human Rights (ECtHR).
  • Section 3 HRA provides that courts must give effect to UK legislation in a manner that is compatible with the ECHR.
  • If not possible to interpret in accordance with section 3, section 4HRA enables the higher courts to grant a declaration of incompatibility stating that a statutory provision in inconsistent with the ECHR.

In R v A (No.2) [2001] UKHL 25;[2002] 1 AC 45 the defendant was accused of rape, but argued consent as a defence, arguing he had had previous sexual relations with the victim. Section 41 of the Youth and Criminal Justice Act 1999 introduces the concept of four 'gateways', which are the four exception to a general prohibition on the admission of sexual history evidence of the complainant in rape trials. In R v A (No.2) the accused argued that although none of these four gateways would allow in the evidence of a prior sexual relationship between the accused and complainant. The accused introduced Article 6 of the ECHR on the right to a fair trial, arguing that if the sexual history evidence was withheld from the jury, then he would not receive a fair trial. The case illustrates how legislation introduced to promote complainants in rape cases from coming forward and reporting the crimes committed against them, and hence serving a public function, can still be overruled when the human rights of the accused are prioritised.

The current Conservative government have stated that they may repeal the HRA and have even brought into question the UK's membership of the ECHR. As yet there appear to be no clear proposals as to how it would be replaced, by domestic legislation. It is important in the light of the vote in the UK referendum that the UK will leave the EU, not to confuse this issue with the country’s membership of the ECHR. Subsequent governments have not been happy with the way that the ECtHR has overruled decisions of UK courts or ruled legislation to breach of human rights; some see it as a threat to sovereignty. e.g. Chahal v UK [1996] 23 EHRR 413, and Saadi v Italy [2008] ECHR 179,the ECtHR found that terrorist suspects could not be deported if there was a 'real risk' of torture were they to be returned to a country of nationality.

Examination Consideration

Be careful to understand the distinction between the European Human Rights Court in Strasbourg and the Court of Justice of the European Union in Luxembourg.

The European Union

Although the UK's membership within the European Union is currently in question, the EU is still of considerable relevance in UK law and governance. As a result of the economic devastation of the European continent after the Second World War, allied powers became determined to establish a "kind of United States of Europe" (Winston Churchill, 1946). Three European Communities were originally established: the European Economic Community (EEC), the European Atomic Energy Community (Euratom) in 1957 (established under the Treaty of Rome) and the European Coal and Steel Community (ECSC) in 1951. The UK did not join the three communities until 1973.

The reference to the 'European Community' did not come about until the Treaty on European Union (the Maastricht Treaty), which also renamed the EEC Treaty (Treaty of Rome) the EC Treaty. The EC Treaty was later to become known as the Treaty on the Functioning of the European Union (TFEU). Throughout the Maastricht Treaty and the TFEU, the word 'community' has now been replaced by 'union'. Reforms enacted through the Lisbon Treaty to the institutions of the EU now include: the European Council; the Council of the EU; the Commission; the European Parliament and the Court of Justice of the European Union (CJEU).

The European Union as exists today was established in 1992 during a meeting of the heads of state or government of the Member States in which the TEU was signed at Maastricht in the Netherlands. The TEU made significant changes to the provisions of the EC Treaty, including strengthening the powers of the European Parliament and establishing the foundations of the economic and monetary union. The first stage removed barriers to movement of capital within EU Member States and established the single market. Stage 2 aimed to bring about the convergence of European economies and began on 1 January 1994. Stage 3 has involved the establishment of the common exchange rate for members of the EU and the single currency, the Euro.

The UK never joined the single currency due to the sensitive political nature of the issue and the requirement that the UK phase out its currency and introduce the Euro. Since the EU referendum of 23 June 2016, citizens of the UK voted by a margin of 52% to 48% to leave the EU. The future relationship between the EU and the UK is currently in a state of considerable uncertainty. Very significant constitutional consequences have arisen as a result of the vote. The UK will need to decide to what extent it wishes to disentangle its domestic laws from EU law and how much will remain. On leaving the EU, the UK of course will no longer have any involvement in EU policy, the content of EU law, nor will it contribute members to the EU institutions.

The Lisbon Treaty, which was signed on 13 December and 2007 and entered into force on 1 December 2009, was the source of significant constitutional reform within the EU. Judicial review proceedings were brought in R (on the application of Wheeler) v Office of the Prime Minister (2008) in which the claimant sought a declaration that the UK government had acted unlawfully on deciding not to hold a referendum on the Lisbon Treaty.  The claimant was defeated on the fact that the promise of referendum by the Labour government was made in relation to the Constitutional Treaty, which was not adopted. The claimant had also found to show that the effect of the Lisbon Treaty was equivalent to that of the Constitutional Treaty. The Lisbon Treaty became UK law by virtue of the European Union (Amendment) Act 2008.

Examination Consideration

Critical analysis of the doctrine of parliamentary sovereignty in relation to EU supremacy.

The European Council

The European Council has no legislative function, but is to 'define the general political directions and priorities of the [EU]'(Art 15(1) TEU). It is made up on heads of state or government of Member States, its President, and the President of the Commission. The Presidents role is to chair and progress the work of the European Council, to facilitate cohesion and consensus and to report to the European Parliament after Council meetings. The President also represents the Council on issues concerning common foreign and security policy.

The Council of the EU

The Council is the hardest of the EU institution to place within the three branches of government advocated within the separation of powers doctrine. The Council considers legislation initiated by the Commission.

The Commission

The Commission carries out both executive and legislative functions. It is made up of a Commissioner from each of the Member States, who looks after a particular area of responsibility (e.g. trade and industry, competition). The Commissioner is required to act independently of the member State who has appointed him or her. The Lisbon Treaty agreed to reduce the number of Commissioners by a third by November 2014 in recognition of the growing membership of the EU and the impact that this had on the number of members of the Commission.

The Parliament

The European Parliament consists of directly elected citizens of the Member States to exercise powers endowed upon it under the TEU and TFEU. In the UK, elections to the European Parliament are governed by the European Parliamentary Elections Act 2002. The Act provides for a system of proportional representation for election of MEPs. Article 14(2) of the TEU provides that the European Parliaments membership shall not exceed 750, in addition to the President of the Commission.

The European Parliament possesses an 'ordinary legislative procedure' and a 'special legislative procedure'. The former applies to a co-decision procedure set out in Article 294 TFEU. This procedure is invoked with the Commission submits a proposal for legislation to the Parliament and the Council.

The Court of Justice of the European Union

This court was formerly known as the European Court of Justice (ECJ); it became known as the CJEU on the adoption of the Treaty of Rome in 2009. The CJEU sits in Luxemburg and its membership consists of one judge per member state (Art 19(2) TEU). The rules of the court allow it to sit as the full court or in chambers of as a Grand Chamber. The primary function of the Court is to ensure that in the interpretation and application of the Treaty, the law is observed.

Legislative Functions

Executive Functions

Judicial Functions



Court of Justice of the EU



Court of Auditors

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