Public law

Public law is the part of law that governs relations and affairs between legal persons and a government, between different institutions within a state, between different branches of governments, as well as relationships between persons that are of direct concern to society. Public law comprises constitutional law, administrative law, tax law and criminal law, as well as all procedural law. Laws concerning relationships between individuals belong to private law.

The relationships public law governs are asymmetric and unequalized. Government bodies (central or local) can make decisions about the rights of persons. However, as a consequence of the rule-of-law doctrine, authorities may only act within the law (secundum et intra legem). The government must obey the law. For example, a citizen unhappy with a decision of an administrative authority can ask a court for judicial review.

The distinction between public law and private law dates back to Roman law, where the Roman jurist Ulpian (c. 170 – 228) first noted it. It was later^[when?] adopted^{[by whom?]} to understand the legal systems both of countries that adhere to the civil-law tradition, and of those that adhere to common-law tradition.

The borderline between public law and private law is not always clear. Law as a whole cannot neatly be divided into "law for the State" and "law for everyone else". As such, the distinction between public and private law is largely functional rather than factual, classifying laws according to which domain the activities, participants, and principal concerns involved best fit into. This has given rise to attempts to establish a theoretical understanding for the basis of public law. For example, an individual entering into contract with a government for a service would usually be within private law even if the State is involved.

The distinction between public and private law was first made by Roman jurist Ulpian, who argues in the Institutes (in a passage preserved by Justinian in the Digest ) that "[p]ublic law is that which respects the establishment of the Roman commonwealth, private that which respects individuals' interests, some matters being of public and others of private interest." Furthermore, he defines public law as the law concerning religious affairs, the priesthood, and offices of the State. Roman Law conceived of the law as a series of relationships between persons and persons, persons and things, and persons and the State. Public law consisted of the latter of these three relationships. However, Roman lawyers devoted little attention to this area, and instead focussed largely on areas of private law. It was, however, of great importance in Teutonic society, as noted by German legal historian Otto von Gierke, who defined the Teutons as the fathers of public law.

Drawing a line between public and private law largely fell out of favor in the ensuing millennium, though, as Ernst Kantorowicz notes, Medieval jurists saw a concern with the Roman conception of the res publica inherent in the legal fiction of the king's two bodies. However, legal philosophers during this period were largely theologians who operated within the realm of Canon Law, and were therefore instead concerned with distinctions between divine law, natural law, and human law. The "public/private" divide in law would not return until the 17th and 18th centuries. Through the emergence of the nation-state and new theories of sovereignty, notions of a distinctly public realm began to crystalize. However, the claims made by monarchs, and later parliaments, to an unrestrained power to make law spurred attempts to establish a distinctly private sphere that would be free from encroaching State power in return.

Traditionally, the division between public and private law has been made in the context of the legal systems found in Continental Europe, whose laws all fall within the tradition of civil law. However, the public/private divide does not apply strictly to civil law systems. Given public law's emphasis on aspects of the State that are true of all systems of government and law, common law legal systems acknowledge, even if they do so unconsciously, that actions which must be prohibited by the State need not necessarily be prohibited for private parties as well. As such, legal scholars commenting on common law systems, such as England and Canada, have made this distinction as well.

For many years, public law occupied a marginal position in continental European law. By and large, private law was considered general law. Public law, on the other hand, was considered to consist of exceptions to this general law. It was not until the second half of the twentieth century that public law began to play a prominent role in European society through the constitutionalization of private law, as well as the development of administrative law and various functional fields of law, including labor law, medical law, and consumer law. Though this began to blur the distinction between public and private law, it did not erode the former. Instead, it elevated public law from its once marginal state, with an acknowledgment that there are few, if any, areas of the law that are free from potential State intervention. In Italy, for example, the development of public law was considered a project of state-building, following the ideas of Vittorio Emanuele Orlando. Indeed, many early Italian public lawyers were also politicians, including Orlando himself. Now, in countries such as France, public law now refers to the areas of constitutional law, administrative law, and criminal law.