Law, from Latin legem, meaning ‘a thing that is made or done’, is a system of rules created and enforced by social and governmental institutions to govern behaviour. Law varies in complexity from country to country. Many legal systems use statutes (laws passed by a parliament or similar legislature) alongside judge-made common law. The statutory law layer is built on top of the older common law foundation, and judges still retain the authority to “legislate from the bench”.
Some systems are complex: the U.S., for instance, has a federal court system with separate judicial and legislative branches. This is one way to ensure that no single person can gain absolute power, as James Madison wrote in The Federalist Papers. This concept of separation of powers is also used in other countries with constitutional laws.
Other complexity arises from the fact that laws are largely judge-made and, in many cases, based on the individual experiences of judges. The decisions of judges are compiled into a collection known as case law. This is the basis of common law systems, while in civil law jurisdictions, laws are set out in codes. Judges’ decisions are not binding on judges in other jurisdictions, and even within a single jurisdiction, appellate court decisions have more weight than lower courts’ decisions.
The development of laws has not always been logical: they have often depended on felt necessities, popular moral and political theories, and intuitions of public policy, avowed or unconscious. This is why legal history is a useful academic subject.
A wide range of fields are concerned with law: labour law, for example, covers the tripartite relationship between worker, employer and trade union; criminal law is about a citizen’s right to a fair trial and a hearing before a judge; civil procedure is about how a court conducts itself during a trial or appeal, such as which materials can be admitted into evidence; competition law looks at business practices that affect market prices; and biolaw concerns the intersection of law and the biological sciences.
The practice of law involves a specific professional qualification (see legal profession and legal education), and a distinct ethical identity is conferred through specified procedures (see legal ethics). Contemporary law also reflects the social and economic issues that society faces. These include the impact of technology and globalisation, whilst terrorism and asylum pose particular problems for law’s societal role. Max Weber and others reshaped thinking on the extension of state power over citizens, and modern military and policing power over their daily lives presents special challenges for law’s accountability that Locke or Montesquieu could not have foreseen. See also the articles on civil society and on law’s relation to the political system.