This article explains, with rudimentary depth, the various ways the law can be classified. This article serves to introduce one to the various fields of law, and is by no means an exhaustive explanation.
The law is a very broad topic, and deals with a diverse issues: traffic violations, the right to privacy, the right to protest and the penalisation of murder. Its jurisdiction can vary in size, from provinces within a country to over a hundred countries. The different fields of law are dealt with by different types of legislative bodies, courts, lawyers, law enforcement agencies, etc.
Let's first classify law based on its association with a country.
The law is first classified into National (state) law and International Law. National law only has jurisdiction within the sovereign territory of that nation and its courts. It is created by the legislature of that country. International law has jurisdiction over all countries that are party to (i.e. have ratified) that law. It is created by an international body such as the European Union or binding resolutions of the United Nations Security Council.
International Law is further divided into two. Generally, private law is the law of relations between 2 (or more) private parties (or states), such as contracts and torts. It requires the parties to perform an explicit action to invoke private law (such as entering a marriage or a sale deed). Public law is the law of relations between individuals and the state. International public law is the law of relations between states. Public law does not generally require an explicit action to be invoked.
Public International Law deals with the conduct of nation-states and their relations with other states, and to some extent also with their relations with individuals, business organizations, and other legal entities. Public international law does not have a conventional enforcement framework, so no worldwide policing organization exists to ensure that treaties are followed. Instead, nations subject themselves to international law by adhering to treaties, and by accepting customary laws and agreed-upon general principles of law. Private International Law describes the body of law surrounding which law governs when there is a conflict between citizens or companies of different countries. In recent years, there has been an effort to create a more unified system of private international law, and treaties and conventions, model laws, legal guides, and other instruments may also be used. Private international law tends to be subject-specific; currently, there is no well-defined body of private international law, but certain subjects such as contracts or family law may have their own governing rules.
National law is also classified similarly.
Public Law is further split into 3 categories.
Constitutional Law is a body of law which defines the role, powers, and structure of different entities within a state: the executive, the parliament (legislature), and the judiciary; as well as the basic rights of citizens, the relationship between the central government and state, provincial, or territorial governments. Not all nation-states have codified constitutions, though all such states have a jus commune (law of the land). Constitutional law deals with the fundamental principles by which the government exercises its authority. In some instances, these principles grant specific powers to the government, such as the power to tax and spend on the welfare of the population. Other times, constitutional principles act to place limits on what the government can do, such as prohibiting the arrest of an individual without sufficient cause.
Administrative Law is the law that governs the administrative actions. It determines the organisation, powers and duties of administrative authorities. It includes law relating to the rule-making power of the administrative bodies, the quasi-judicial function of administrative agencies, legal liabilities of public authorities and the power of the ordinary courts to supervise administrative authorities. It governs the executive and ensures that the executive treats the public fairly.
Criminal Law is a system of law concerned with the punishment of offenders of the law. Criminal laws become applicable once such a violation has occurred, and until then, serve to deter and prohibit the same, by threat of penalisation. These are “duty imposing” laws. Penalisation for criminal law violations is severe, and in some countries, can include the highly debated death penalty.
Private National Law is also of 3 categories.
Law of Property and Contracts: The law governing property and contracts is one category of private national law. In the legal sense, one's property is that which one has the right to enjoy and to dispose of, in an absolute manner, as one thinks is fit. It includes both corporeal things (land and furniture) and incorporeal things (copyrights and patents). A contract is a legally enforceable agreement that creates, defines, and governs mutual rights and obligations among its parties. A contract typically involves the transfer of something of value, or a promise to transfer it at a future date.
Law of Persons is concerned with the determination of legal subjectivity, the rights and duties associated with legal personality, and issues of legal status. It identifies natural persons (human being possessing natural personality) and legal persons (a legal person has a real existence but its personality is fictitious, such as a registered company).
Law of Obligations and Torts: The law of obligations is one branch of private law under the civil law legal system and so-called "mixed" legal systems. It is the body of rules that organizes and regulates the rights and duties arising between individuals. The specific rights and duties are referred to as obligations, and this area of law deals with their creation, effects, and extinction. The concept of tort law is to redress a wrong done to a person and provide relief from the wrongful acts of others, usually by awarding monetary damages as compensation. There are three main categories of tort law, including suits alleging negligence, intentional harm, and strict liability.
Why must one know the classifications of law?
The category of law in question for a dispute would decide which level and type of court would handle the case, what the scope of penalisation is, whether the case would be presided over by a judge, a bench of judges or a jury and more. For example, in India, the National Company Law Tribunal (NCLT) adjudicates issues relating to companies and the Armed Forces Tribunal related to issues faced by members of the armed forces, including commission, appointments, enrolments and conditions of service.