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Updated: May 8, 2023

Introduction to Constitutional Law

Constitutional Law

Law is generally divided into two different segments: public law and private law. While public law regulates relationships between the state and private individuals, private law generally regulates legal relationships between private persons. Public law is comprised of constitutional law which regulates the functioning of the state and administrative law which governs the relationships between the state and private individuals.

The distinction between private and public law

As stated above, private law is in fine a branch of the law that is concerned with the relationship that individuals have with one another. It should be noted that the notion of private persons encompasses both individuals and legal persons that are private entities (companies, associations etc.).

Private law will apply, for example, when an individual agrees to purchase a car and forms a legally binding contract with another person. Private law also regulates defamatory cases where for example, an individual sues a neighbour for making slanderous accusations about his past.

It is also worth noting that private persons can have legal relations of private law transactions with public persons (in this context and for the present purposes, the term public persons refers to the state in general including the government, local authorities etc.). For example; a private legal person, such as a company, can have private legal transactions with local authorities for the purposes of providing public services. Similarly, an individual may sue a public person in the law of negligence for having acted carelessly and caused harm.

However, these legal relationships, given that they involve the state, will generally imply a public law dimension. Accordingly, special rules will be applied to the state in order to not treat as an ordinary private individual defendant. In this connection, it is important to note that the line between public and private law may sometime be difficult to draw given that there is no absolute distinction. In this regard, Lord Wilberforce in Davy v Spelthorne Borough Council (1984) 1ac 262, commented: “the expressions “private law” and “public law” are convenient expressions for descriptive purposes. In this country they must be used with caution.”

Public law subsumes constitutional and administrative law. It is the branch of law that focuses on the power of the state as well as its structure and organization. It deals with the location of state powers, how they are exercised and controlled and how it could impact on individuals. One of the questions raised by public law is to determine how the institutions relate between them and in relation to individuals.

At this stage, it is important to note that criminal law, although it has a public law dimension, has historically been taught separately. Indeed, the public law dimension comes from the fact that the society as a whole also suffers from an offense. Hence, public authorities are entitled to punish authors of criminal acts. Therefore, it is not wrong to say that the broad term of public law embraces criminal law, although it is usually taught in a different module.

The distinction between constitutional and administrative law

Although constitutional and administrative law form part of the generic term of public law, a distinction between them should be drawn. Constitutional law relates to the rules enshrined by a constitution. A precise definition of the term constitution will be given in the following chapters. However, for the present purposes, a constitution is a set of fundamental rules regulating the powers of the state and determining the relations between its institutions and individuals.

Constitutional law concerns various aspects of the structure and organization of the state such as the recognition of the principal institutions of the state (parliament, government and the courts) but it also confers there to these institutions specific roles and functions, determines their nature and the extent of their powers.

In addition to this, constitutional law sets procedures and mechanisms to oversee, regulate and check the powers conferred to the different institutions. This is usually done by the way the constitution organizes the way of how the main institutions relate to one another.

The constitution generally enshrines the fundamental rights of the individual of the state and how these rights can be judicially protected from infringements of the state.

In contrast with constitutional law, administrative law is generally concerned with the law relating to the administration/government. The government and its administration are invested with extensive prerogatives to provide services such as education and to adopt regulations to implement its political program. Administrative law therefore ensures that the administration is strictly acting within the limits of its mandate.

This branch of the law deals with different control mechanisms that can be judicial (for example the judicial review) or political (for example parliamentary control with ombudsman). Although a clear-cut distinction between administrative and constitutional law is impossible to draw, it should be noted that where constitutional law concerns the main structure and organisation of the state, administrative law relates rather to the concrete exercise of the governmental powers. For the purposes of clarity of the analysis, constitutional law and administrative law will be studied separately in the next chapters.

Recent developments in constitutional and administrative law

The general election victory by the conservative party, led by Margaret Thatcher in 1979 was a contextual starting point for many of the recent developments of the UK constitutional and administrative law. Margaret thatcher used the methodology of ‘new public management’ (NPM), an approach which rejected traditional bureaucratic methods and structures in favour of market-based and business-like regimes of public service.

Since then, the different administrations have been driven by the perceived need for greater efficiency and accountability of public action. For years the division between the public and private sectors in the UK had been clear-cut. Traditionally, the national provision of communications, power and utilities, the health service, and public transport were provided by public bodies, namely local authorities steered by government departments. However, the quest for greater efficiency brought dramatic changes in the nature and the structure of the state. This phenomenon, called privatisation of the public sphere, took two forms.

The first evolution de-nationalised many of the above-mentioned public prerogatives and encourage the state to buy a stake in the new competing private enterprises by buying shares. As a consequence, a great number of companies started competing for the consumer’s business in the provision of energy, telecommunications, and transport. But what were the constitutional implications? Loveland puts it: “in privatising former public services, the government effectively abolishes ministerial responsibility for matters which may have a significant impact on citizens’ lives and welfare. If we regard the constitution as being concerned essentially with structuring both the substance and the processes of the relationship between a country’s government and its citizens, it seems that a major part of the constitution has undergone substantial reform...”[1].

The second form of privatisation was through contracting-out to private providers specific services which were traditionally provided by public entities. For instance, the provision by private companies of ‘outsourced’ services from office-management to staff recruitment; waste-collection to social care; catering, cleaning and laundry provision for schools, hospitals and prisons. Through contractual arrangements to private companies the responsibility logically shifted although a number of problems relating to ultimate responsibility for the discharge of those functions and commensurate dimensions of accountability remained.

In 1988, the cabinet office efficiency unit published a report entitled “improving management in government: the next steps”. The fundamental idea behind the program presented in this report was to improve the accountability of the government and clearly define responsibility of public bodies.

Historically, the constitutional convention of ministerial responsibility meant that government ministers were, in principle and in most cases in reality, accountable for everything done in the name of their department. In serious cases where something had gone badly wrong, this notion of ministerial responsibility could result in ministerial resignations or removal from that particular office.

The 2005 Act also brought about a major change to the UK’s court structure. Historically, the House of Lords had both a legislative and a judicial capacity. To accentuate the separation between legislature and judiciary, however, the constitutional reform act provided for the House of Lords in its judicial capacity to become the new Supreme Court of the United Kingdom, and this change came into effect in October 2009.

One of the other main debates concerns the fundamental constitutional doctrine – that of parliamentary sovereignty, which is the core characteristic of UK’s constitutional identity. The question of the UK parliamentary sovereignty raises another issue of devolution of executive and legislative powers to different parts of the United Kingdom. This question is particularly pertinent with regard to Scotland, following the referendum on Scottish independence in 2014 and the debates following the Brexit; but it also affects wales and Northern Ireland.

The mandate and missions of the administration of the state requires the government, local authorities or courts to use special public prerogatives which enables local authorities’, for example to purchase property compulsorily or courts to impose imprisonment. These powers are, of course, granted to public authorities almost exclusively by means of statutes which – at least in theory – delineate the extent and scope of those powers.

Judicial review is often seen as the major way in which the legality of administrative action is controlled. This is an approach which stresses the part played by the law in the control of administrative activities, and is underpinned by the doctrine of ultra vires which imposes on public bodies the obligation to lawfully act within the limits of the powers given to it.

Historically, the massive expansion of the administrative state over the last hundred years, with the state taking on responsibility for education, health provision, energy, social services and housing; logically imposed on public bodies to operate within the bounds of legality. Consequently, administrative law is defined as the legal framework through which public bodies may deliver better, in other words more transparent and fair, public services.

Those in favour of these ideas are followers of the green-light theory. Taggart explained it: “green light theorists looked to the truly representative legislature to advance the causes of workers, women, minorities and the disadvantaged. For them, the role of law was to facilitate the provision of programmes of public services. Parliament was trusted to deliver socially desirable results”. In this respect, the functions of administrative law are to facilitate and to regulate of public bodies.

In the 1990s has emerged a new function to administrative law which we may term a ‘rights-based’ approach. The achievement of this phenomenon has resulted on the incorporation of the European convention on human rights into English law through the human rights act 1998. This approach stresses the need not for a reactive verdict on the legality or otherwise of administrative action, but rather on the proactive development of standards of legality designed to protect human rights and prevent abuse of power. Like red-light theory, this view sees a central role for the judiciary in analysing the impact of governmental actions on rights.



[1]Ian Loveland, Constitutional Law, Administrative Law and Human Rights, (4th edn, Oxford University Press, 2006) pp. 24-5


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