The Doctrine of Separation of Powers in the UK

The doctrine of separation of powers is premised on the separation between the organs of the state: legislature, judiciary and the executive, which means that they perform their respectively divided functions independently and without interference from each other. The constitutional system in the UK has never applied the principle of separation of powers strictly; rather separation of powers has been loosely applied until the enactment of the Constitutional Reform Act 2005 (CRA 2005). Indeed, it has been argued that no reputed academic writer would claim that the principle of separation of powers is central to the British constitution. Some of this has changed since the passage of the CRA 2005, which introduced reforms including application of the doctrine of separation of powers in the UK. Irrespective of these reforms, it can be said that the powers are as separate as they can be under the English constitution.

At the outset, it may be acknowledged that the principle of separation of powers has not been an essential part of the English Constitutional law. Nevertheless, with respect to separation of powers, there are two reforms that were brought in by the CRA 2005. The first reform relates to the cessation of the office of Lord Chancellor as the head of judiciary and the second relates to the establishment of the Supreme Court as the highest court. The purpose of these reforms is to bring about the complete separation of the judiciary from the executive and the legislature. In other respects, there are interlinks between executive and the legislature, which means that with respect to these two organs, there is continuation of the constitutional conventions which interlink these organs.

Prior to CRA 2005, if separation of powers was applied in some domain more properly, it was in separating the powers of judiciary from executive and legislature. Examples of this can be found in a number of authorities that saw the courts emphasising separation of powers between the judiciary and the legislature and executive. In R (Anderson) v Secretary of the State for the Home Department, strict separation of powers was held to be a strong principle of governance in the UK. In Pickin v British Railways Board, application of the principle of separation of powers was held to be a part of the application of principle of parliamentary sovereignty. In R v Hinds, separation of powers between the judiciary on one hand and the legislature and executive on the other was held to be a matter of fact.

Despite the authorities noted above, the principle of separation of powers was not as strictly applied even with respect to the judiciary. This is most particularly exemplified in the role played by the Lord Chancellor as part of executive, legislature and judiciary. Prior to CRA 20065, the Lord Chancellor was the head of the judiciary, the Speaker in the House of Lords and a senior cabinet minister. This was considered to be an example of how UK’s constitutional law deviates from the principle of separation of powers with respect to the judiciary’s separation from the legislature and executive. CRA 2005 brought some important changes in this regard. The Lord Chief Justice is now the President of the Courts of England

Dawn Oliver and Gavin Drewry, The Law and Parliament (Cambridge University Press 1998).
S de Smith and R Brezier, Constitutional and Administrative Law (8th ed, Penguin 1998) 18.
Dawn Oliver and Gavin Drewry, The Law and Parliament (Cambridge University Press 1998).
Roger Masterman, The Separation of Powers in the Contemporary Constitution (Cambridge University Press 2010) 219.
R (Anderson) v Secretary of the State for the Home Department [2002] UKHL 46; also, DPP of Jamaica v Mollison [1979] Crim LR 111.
Pickin v British Railways Board [1974] AC 765.
R v Hinds [1979] Crim LR 111.

and Wales and head of the Judiciary. Moreover, the CRA 2005 also led to the establishment of the Supreme Court which is now the highest court in England and Wales and replaces the House of Lords in that respect.

Clearly, with respect to the judiciary the principle of separation of powers has been applied in a stronger way than before after the passage of CRA 2005. Nevertheless, it may be said that the powers are as separate as they can be under the English constitution. This is so because the English constitutional system has traditionally seen an intertwining of the organs of the state. The executive and the legislature are still interlinked in this way because the Prime Minister and Cabinet of Ministers are also Members of Parliament. It has been said that the UK has evolved a unique system where fusion of functions of organs instead of separation is emphasised. In this longstanding system, separation of powers in a strict sense is difficult to achieve.

While it has been possible to apply a less diluted form of separation of powers with respect to the judiciary and its separation from the legislature and the executive, it will not be easy to enact changes that leads to separation of executive and legislature. Even with respect to judiciary some aspects of pure separation of powers are not applied because these would be contrary to the constitutional conventions. For instance, judicial lawmaking is an accepted convention which has led to the common law. Delegated legislation is also a well-entrenched part of executive functioning in the UK. With respect to the legislature and the executive, there are some constitutional conventions, like the office of the Prime Minister, which are long-standing, and which will be difficult to supplant with reforms that are premised on a pure separation of powers. Moreover, the constitutional changes in the UK are more driven by the practical necessity and it is difficult to foresee a situation where it will become practically necessary to make further reforms on the basis of pure separation of powers. Instead, the overlap between Parliament and Executive has been considered to be useful for establishing accountability of the executive in the Parliament. Other dilutions of the separation of powers principle, such as delegated legislation are also considered to be useful. Therefore, what has been achieved by the CRA 2005, can be said to be as much of the application of separation of powers as is possible or desirable in the UK.

To conclude, the CRA 2005 has seen the Parliament take an effective step to separate the judiciary from the legislature. This has been done by creating a new office in the Lord Chief Justice which replaces the Lord Chancellor’s office and by creating the Supreme Court for replacing the House of Lords as the highest appellate court in the land. However, further changes to establish more separation is unlikely given the strength of the constitutional conventions.

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Constitutional Reform Act 2005, Section 7.
Ronald J Krotoszynski, ‘The separation of legislative and executive powers’ in Tom Ginsburg and Rosalind Dixon (eds) Comparative Constitutional Law (Edward Elgar 2011) 248.
Walter Bagehot, The English Constitution (Chapman & Hall 1867) 12.
Mark Ryan and Steve Foster, Unlocking Constitutional and Administrative Law (Routledge 2014) 77.
Ibid.

Table of Cases

DPP of Jamaica v Mollison [1979] Crim LR 111.

Pickin v British Railways Board [1974] AC 765.

R (Anderson) v Secretary of the State for the Home Department [2002] UKHL 46

R v Hinds [1979] Crim LR 111.

Bibliography

Books

Bagehot W, The English Constitution (Chapman & Hall 1867).

de Smith S and Brezier R, Constitutional and Administrative Law (8th ed, Penguin 1998).

Krotoszynski RJ, ‘The separation of legislative and executive powers’ in Tom Ginsburg and Rosalind Dixon (eds) Comparative Constitutional Law (Edward Elgar 2011).

Masterman R, The Separation of Powers in the Contemporary Constitution (Cambridge University Press 2010).

Oliver D and Drewry G, The Law and Parliament (Cambridge University Press 1998).

Ryan M and Foster S, Unlocking Constitutional and Administrative Law (Routledge 2014).