Law is the body of rules created and enforced through social or governmental institutions to regulate behavior. These rules can be made by a collective legislature in the form of statutes, by the executive through decrees and regulations, or by judges through case law. Law can also refer to a set of principles derived from empirical science (such as the law of gravity) or to social science (the law of supply and demand). In addition to its practical applications, law is a rich source of scholarly inquiry in legal history, philosophy, economic analysis and sociology.
The primary functions of law are to establish standards, maintain order, resolve disputes and protect liberties and rights. In addition, law ensures that the government, police and public officials carry out their duties in a fair manner. However, different legal systems serve these purposes differently. For example, a nation ruled by an authoritarian regime may keep the peace and maintain the status quo, but it often oppresses minorities and restricts political opponents. A democratic nation may be able to achieve some of these goals better through a representative democracy, but it must still balance the competing interests of its constituents.
Moreover, even within a country, the law is not always perfectly clear. For example, a court may interpret a statute in a way that differs from the meaning originally intended by the legislator. A court’s decision is then used as a precedent for future cases, forming a body of law known as case law. Similarly, a judge’s instructions to the jury at trial are based on the law as it applies to the facts of the particular case before them.
Another important aspect of law is the process by which it is adopted, administered, adjudicated and enforced. The law must be publicly available and stable, and the processes by which it is interpreted and applied must be accessible, fair and efficient. The law must also provide an adequate guarantee of human rights, property rights and freedom of contract. In this regard, the modern military, policing and bureaucracy pose special challenges for accountability that earlier writers such as Locke or Montesquieu could not have foreseen.
The study of law is usually divided into the fields of criminal law, civil law and administrative law. The first deals with crimes and the punishment of criminals, while the second deals with disputes between citizens and the enforcement of contracts. The third field, administrative law, covers the activities of government agencies, such as regulating commerce, enforcing property rights and settling disputes. A more specialized area of law is space law, which addresses the relationship between human activity and outer space. The study of law also includes the theory of legal science and the methodology of research in the field. The latter involves identifying and studying relevant primary and secondary sources, such as law reviews, legal dictionaries and treatises. It also involves examining how law changes over time. Legal research is a vital component of any legal job, whether as a researcher or practitioner.