We mean in the second place, when we speak of the "rule of law" as a characteristic of our country, not only that with us no man is above the law, but (what is a different thing) that here every man, whatever be his rank or condition, is subject to the ordinary law of the realm and amenable to the jurisdiction of the ordinary tribunals.
Sounds all fine and dandy. But life's a bit more complex than that. There are a number of problems in treating the "governors" and the "governed" (ie public law actors and private law actors) in the same way. Some of these issues are canvassed by Cane in the following extract (Peter Cane, Administrative Law (4ed, Oxford University Press, Oxford, 2004), 11):
A question that does deserve attention, however, is why a distinction is drawn between public and private law, public law applying to public activities, and private law applying to private activities. An obvious but not very informative reply to this question might be: because we want to regulate the performance of public functions in accordance with a different legal regime from that which regulates private activities. By way of explanation, it is possible to suggest a number of reasons for this. First, because institutions of governance have the job of running the country they must have some functions, powers, and duties which private citizens do not have; obvious examples are the waging of war and the issuing of passports. Secondly, because of the very great power governmental institutions can wield over its citizens (most particularly because government enjoys a monopoly of legitimate force), we may want to impose on them special duties of procedural fairness that do not normally apply to private citizen, and special rules about what organs of governance may do and decide. Thirdly, because certain institutions of governance have a monopoly over certain activities and the provision of certain goods and services, it might be thought that the exercise of such powers ought to be subject to forms of 'public accountability' to which the activities of private individuals are usually not subject. Fourthly, because the courts are themselves organs of governance (i.e. they perform public functions), the view they take of their proper role when dealing with the exercise of public power is different from the way they view their role in relation to purely private matters. In relation to the affairs of private citizens the courts are the primary organs for interpreting, applying, and enforcing the law By contrast, when they are dealing with matters involving other organs of governance the courts take a more restrained view of their role. Parliament is largely free of judicial control; and under the rules of administrative law other organs of governance enjoy a greater or lesser degree of autonomy from judicial control. This judicial restraint is partly a function of the doctrine of separation of powers...A fifth reason for distinguishing between public and private law arises out of the fact that although governments have certain distinctive functions (such as national defence), many of the things they do are also done by private citizens. Governments make (and sometimes break) contracts just as private individuals do; governments own property in the same way as private citizens; governments also sometimes commit torts. The relevant bodies of law -the law of contract, tort, and property-are central areas of private law, developed to regulate dealings between citizen and citizen. Should these regimes of private law apply equally to government contracts, government property, and government torts, or should there be a law of public contracts, public property, and public torts? As we will see in Part II, the answer which the courts have given to this question is neither an unqualified 'yes' nor an unqualified 'no'. There are, for example, some 'public law' rules of liability in contract and tort. The argument against having a special public law of contract, tort, and so on was most famously put by Dicey. In his view, it was a great strength of English law that government officials were subject to basically the same laws as private citizens to the extent that these covered the activities of government. In this way the law ensured that the government was given no unfair privileges or advantages over its citizens. An argument which pulls in the opposite direction is this: even when a government agency is, for example, making contracts, it is doing so in some sense as representative of the citizenry at large and must bear the interests of the community as a whole constantly in mind. It might sometimes harm the public interest to subject government to rules designed to deal with cases in which the political responsibilities of government are not at issue. On the other hand, the government is a very powerful institution, and we may feel that private citizens need protection, in their dealings with government, against the operation of this power (even in the absence of abuse) by modification in their favour of the rules which govern the citizens dealings with other citizens when these rules are applied to dealings between citizen's and government. The distinction between public law and private law can, therefore, be used either to accord government special privileges, or to impose on it special responsibilities and duties and to subject it to special controls. Three examples will illustrate the importance of whether a particular activity is regulated by public law or private law. Take government contracting first. As a general rule, private individuals are free to refuse to buy goods or services from a business on the ground that the business has trading links with a country which is under the control of a government of which they disapprove. This follows from the principle that individuals are free to contract or not to contract with whomever they please. Do (and should) government bodies enjoy the same freedom? We will see in Chapter 12 that as a matter of common law, central government enjoyed the same freedom of contract as a private individual. However, now this freedom to contract is heavily circumscribed by rules based on EC law which, for all practical purposes, prohibit central government and other 'organs of the state' from refusing to contract with someone for 'non-commercial' or 'non-economic' reasons. Another illustration is provided by the police. The police, of course, have extensive powers of arrest; but these powers are not unlimited. In particular, a police officer can be sued for wrongful arrest and false imprisonment (which are forms of the tort of trespass to the person) if he or she arrests a person without a justification recognized by law The application of the law of tort (which is, of course, part of private law) to the police is a reflection of the fact that constitutionally, police officers are not government officials but enjoy independence from the government of the day. On the other hand, police officers are not the same as private security guards, and they enjoy powers of arrest more extensive than those possessed by ordinary citizens. Apparently because of the public nature of policing activities, the House of Lords has held that in a tort action for false imprisonment the question, of whether the police acted reasonably in arresting a person suspected of having committed an arrestable offence, is to be judged according to public law principles of reasonableness. The impact of this decision is to give the police greater freedom to arrest in the public interest and correspondingly to encroach upon the liberty of the individual. It is also clear that decisions and actions of the police can be challenged by way of judicial review. As a third example, consider the case of Swain v Law Society. The Law Society ran a compulsory liability insurance scheme for solicitors under statutory powers. The Society placed the insurance with commercial insurers and received commission for so doing. It decided not to pay out the sums received as commission to individual solicitors as a sort of dividend but to apply them for the benefit of the profession as a whole. Two solicitors challenged this decision but the House of Lords held that since, in administering the scheme, the Society was acting in a public capacity in the interests of all solicitors and members of the public who employed them, the legality of its decision was to be judged according to principles of public law, not private law; and so judged, what the Society had done was a proper use of its statutory powers. The question of whether, as a matter of private law, individual solicitors were entitled to a pay-out, was irrelevant.
As touched on by Cane, this incident highlights one of the tensions in the equality principle. While we aspire to ensure that all people are treated the same, the reality is that the actions of the AOS cannot really be characterised as being the same as ordinary citizens. The police officer was in a context that ordinary citizens would not find themselves - being deployed with arms to apprehend a renegade and defend the public.
But that's not to say the police are immune from accountability for such actions. Even if the police officer is not charged, he or she - and the police generally - will be held to account through other processes; processes which are designed to take into the different circumstances and context of the action and public character of the actor.