Law is a set of rules created to ensure that a society is orderly. It serves four principal purposes: establishing standards, maintaining order, resolving disputes and protecting liberties and rights. The study of law involves examining the nature of these laws, how they are enforced and what impact they have on society.
A central issue in the study of law is the role of authority. Lawyers and judges, for example, are considered to be authorities in a court of law. But, unlike other fields of inquiry such as empirical or social science, the law lacks means that enable us to check the validity of authoritative statements (be they comprised in judicial opinions or scholarly literature).
The emergence and evolution of law is closely tied to the evolution of human societies. As a result, the history of law is often the story of the development of human civilizations and their political structures. An authoritarian government, for example, may keep the peace and maintain the status quo but it may also oppress minorities or political opponents. The legal systems of nations vary widely, and some serve the principal functions of law less well than others.
The foundation of the law is found in the constitution and ideology; a country’s political system, and its relationship to its military and economy, are also important. Legal systems differ from country to country as do the rules that govern them. Some legal systems are based on the principle of binding precedent, which requires that the decision of a higher court be followed without exception unless there are compelling reasons and significantly different facts and issues. Other legal systems use legislative statutes to make laws and judicial decisions to establish case law.