Law is the system of rules regulating human behavior and enforceable by a state or other controlling authority. Its principal function is to promote cooperation between members of a society. For example, contract law governs agreements to exchange goods and services; property law defines people’s rights and duties toward tangible and intangible property; torts law compensates individuals for injuries caused by negligence or malicious actions; and criminal law punishes offenses against the community itself. The legal system varies greatly from nation to nation. It is a central element of most modern societies and many have a written constitution that codifies their laws and establishes their authority.
Laws may be formulated by legislative statutes, executive orders or judges’ decisions. In common law systems, court decisions are acknowledged as law on equal footing with statutes and executive regulations; this is known as the doctrine of precedent or stare decisis. In other systems, legislative statutes have a preeminent status over judicial decisions.
Philosophical debates over the nature of law have centered on its normative importance. Early legal positivists, such as Hans Kelsen, argued that the coercive aspect of law is what gives it its normative power; this view has since been disputed by 20th century legal philosophers such as H.L.A. Hart and Joseph Raz, who maintain that coercion is not essential to law’s ability to fulfill its social functions. Other scholars challenge the normative status of any account of law that does not also assert its moral value.