Law is a system of rules that governs people’s interactions with each other and the world around them. It has many functions, but the principal ones are establishing standards, maintaining order, resolving disputes and protecting liberty and rights. The practice of law involves a wide range of subjects, spanning everything from criminal justice to environmental protection. Some fields, such as family law or commercial law, are more concerned with specific types of agreements and relationships; others, like banking or regulatory law, are more concerned with broader economic issues.
In the modern world, most laws are established by governments, but there are also some private laws, particularly those regulating industries such as finance, energy, water, or communications. Private law is often concerned with avoiding social or environmental damage, and it can also be used as a means of competition to incentivize companies to meet high standards. Public law, on the other hand, is concerned with providing basic services such as education and health care. Governments often set minimum standards for these industries, and they also have the power to punish those who break them.
Law can be defined as a system of rules that establishes morality and justifies the exercise of power by the state. This definition reflects the utilitarian theories of John Austin and Jeremy Bentham, but it has been criticized by philosophers such as Jean-Jacques Rousseau and Thomas Aquinas. Other definitions of law include natural laws, which reflect underlying principles that are immutable and unchanging; and moral laws, which incorporate values such as fairness and compassion.
The practice of law requires research and analysis. In a common-law jurisdiction the legislature (Parliament) is not in the habit of enacting detailed statutes on topics such as crimes, torts, contracts and property; instead courts articulate holdings, or general rules, in individual cases. These decisions are then compiled into case law, which can be found in judicial opinions and treatises.
The process of determining what the law is in any particular case is called legal reasoning. This includes ascertaining the facts, locating relevant statutes and case law, extracting principles, analogies or statements by judges, and weighing these factors in light of the particular situation at hand to determine how that court is likely to rule on the subject matter. More recent cases and higher-level legislative decisions are given more weight than earlier or lower-level decisions.
