Law is a body of rules developed by a government or society to regulate crime, trade, social relations, property, finance, and other areas. These rules are enforced by a controlling authority.

Legal theory describes the principles and concepts that underlie law, including how it is created, maintained, and applied. It also explores the relationship between law and other social sciences.

The definition of law is a matter of debate, with many different theories of what makes something a law and how it should be applied in practice. One of the most widely used theories is that law is a set of rules that prescribe obligations or duties and enforce justice, with punishment for violations.

Generally speaking, the term “law” refers to a body of rules that is enacted by a state, often through legislative statutes and executive decrees or regulations. Alternatively, a private individual may create legally binding contracts that bind parties to abide by certain laws.

In most systems, a court decision is considered to be the law of the land if it follows the reasoning that a judge or barrister would give in an earlier case. This principle is known as the doctrine of precedent, or stare decisis.

Custom is also a source of law, but it usually predates legislation and is not always regarded as legally binding. Some argue that customs can be a form of law when they are recognized as such, and others suggest that they must already be regarded as legal norms in order to count as law.

A central question in legal theory is how customs contribute to the content of law, and which customs are relevant to the norms that law prescribes. This question is particularly complex in international law, which varies by region and is based on the principle that all states have equal rights.

Another issue is the method of interpretation. Which method is right (and which reasons or arguments count in favor of that method) depends on what the interpretation seeks – for example, to find the linguistic meaning of a text or to find the best way to resolve a dispute.

The most common approach to interpretation involves an apologetic style, which argues that there is always a clear and consistent meaning of words. This style is influenced by hermeneutical scholarship, which is concerned with understanding the meaning of authoritative texts and applying them to current situations.

There are other approaches, including a policy-oriented style of interpretation that is influenced by the political and social contexts in which the law was made. This type of interpretation has been criticized by some as being judicial law-making, judicial activism, or a form of judicial interference with the wishes of the democratic majority expressed in legislation.

Another approach to interpretation is to identify the specific legal principles and facts that a judge must consider when ruling on a particular case. This involves looking at the language and structure of a text, examining evidence, and considering what is meant by terms in the text, as well as the underlying policy or purpose of the law that the judge must interpret the text to achieve. It is a highly practical approach, and one that equips lawyers and litigants with the tools they need to better understand a judge’s reasoning and present compelling arguments in their defense or attack.