Law can serve many purposes, from keeping a nation’s peace to preserving individual rights and protecting minorities from majorities. It can also promote social justice and orderly social change. Some legal systems are better suited for these purposes than others. In authoritarian regimes, for example, the rule of law is a powerful tool used to suppress political opposition and minority groups. Colonialism has also used law to force peace into a nation, often through conquests. Countries like Britain, Spain, Germany, France, and Holland often built empires based on the principles of law, and the enforcement of law.
Common law
The common law system is based on inductive reasoning, where courts develop rule sets based on experience in real-world cases. This allows them to make decisions that are most helpful to society. Common law also benefits from local knowledge regarding disputes, so judges have an easier time coming up with just rules.
Constitutional law
Constitutional law is a set of rules that determines the powers, role, and structure of various state entities. It defines the role of the executive, the legislature, and the judiciary.
Criminal law
The purpose of criminal law is to prevent wrongdoing and punish the guilty. While it is important to prevent harm, criminal law also addresses non-moral wrongdoing. It is important to protect society from instability by ensuring that people are held accountable for violating laws and other rules.
Administrative law
Administrative law is a branch of public law that regulates agencies of the executive branch of government. It focuses on rule making, adjudication, and law enforcement. Though not a branch of the common law, administrative law has some similarities to it.
Civil law
Civil law is a system of law that originated in mainland Europe, and was later adopted by much of the world. The system is an intellectualized form of Roman law that serves as a primary source of law.
Commercial law
Commercial law focuses on the rights, conduct, and relationships of business people. It is sometimes referred to as trade law or mercantile law. The subject matters of commercial law are often both private and public.
Aviation law
Aviation law is the set of rules that governs aircraft operations. It is a branch of law that combines state and federal laws. It also involves issues related to admiralty, transportation, and corporate/contract law. In the United States, the Federal Aviation Administration (FAA) promulgates aviation laws. These laws are entered into the Federal Register and become part of the Code of Federal Regulations.