Law is a system of rules created and enforced by social or governmental institutions to regulate behavior. Its precise definition is a matter of longstanding debate and it has been variously described as a science and as the art of justice.
The practice of law is an extensive area of study and encompasses many disciplines and professions. In general, law consists of the body of rules and principles that govern human conduct in a society or community and is applied through judicial proceedings. The legal systems of nations differ significantly, but they typically include codifications of common law and statutes, case law (judged decisions), and regulations.
A society requires laws to function properly. These laws may regulate the rights and duties of citizens, provide a means for dispute resolution, or ensure that property is protected. Laws also protect individuals against exploitation and abuse by others or by the government.
Law varies from place to place, but the basic purpose is the same: to regulate and control human behaviour. While some laws are universal, such as the Universal Declaration of Human Rights, most are specific to a particular time and place. For example, adultery is a criminal offence in some countries but not in others.
Even in a well-ordered society, people disagree and conflicts arise. Laws provide a way to resolve these disputes peacefully by allowing judges to decide who is right. Laws also help to preserve property and keep criminals off the streets by punishing them.
The most significant difference between different legal systems is that in “common law” jurisdictions, court decisions are considered to be equal in authority to the statutory law adopted through legislative processes and the regulations issued by executive branch agencies. The principle of binding precedent – or stare decisis – is applied to ensure that courts follow each other’s decisions without needing to provide new reasoning for every decision they make.
In contrast, the legal systems of “civil law” countries, which dominate about 60% of the world’s population, are based on principles and categories established by Roman law with some influence from canon law and local custom. These are largely procedural and did not develop an elite professional legal class.
The most important areas of law are the criminal, civil, and administrative. The former involves prosecutors, police officers, and trials; the latter covers everything from the procedures by which cases are heard to what evidence can be presented at a trial. A broad area of specialization includes immigration law, social security laws, family laws and commercial law. Each of these areas reflects the culture, values and social conditions of the country in which it operates. These factors can have a dramatic impact on the effectiveness and efficiency of a legal system. In some instances, they can impede the ability of the government to meet its fundamental objectives of keeping the peace and maintaining the status quo while protecting minorities against majorities or promoting social change.