Common Law Systems

The US legal system, and other legal systems that emanate from British rule, is a common law system.⁴⁴ Originally, common law meant judge-made law that filled in gaps when there was no written law. Judges looked to prior decisions to determine the unwritten judge-made law and apply it to new cases. However, today, almost all law is in writing and enacted by a legislature as statutes. Many statutes codify established common law, change it, or abolish it altogether, depending on the topic of the law. There are instances in which some unwritten common law is still enforced, but these are rare.

In a common law system such as the one in the United States, the courts’ reliance on precedent is referred to as stare decisis, or a policy of using judicial decisions made in the past to interpret written laws and appropriately apply those laws to the facts in the present case.⁴⁵ The court interprets written laws, and these interpretations and applications of precedent from prior interpretations constitute what is meant by common law today. Precedent is critical for interpreting later cases, and only the same or a higher court can overturn precedent. The court process is adversarial rather than investigatory, with each side trying to win or persuade the court to agree with its perspective.⁴⁶

Common law courts are adversarial; that is, there is a winner-takes-all attitude in the court. In an adversarial system, each side determines the issues and questions it wants the court to resolve, conducts its own investigation, and prepares and presents its own evidence. Each side calls witnesses, who are questioned directly and by cross-examination. Each side brings out information it thinks is pertinent to prove its point. In a criminal case, the police and prosecutor work together closely to establish their viewpoint using the government’s resources. Defendants must rely on their own resources to defend against the charges, either hiring an attorney or using a court-appointed one. In a civil case, the procedures are similar; however, each side must rely on its resources to prove its point. If a jury is present, it decides all factual questions while the judge determines the legal issues and moderates the proceedings. In some cases, the judge can act as a fact finder in place of a jury.

Civil Law Systems

Most of Europe and South America use a civil law system.⁴⁷ A civil law system relies on comprehensive legal codes that contain all laws for the country. Case law—that is, judicial decisions—is secondary to these codes. Decisions are binding only on the parties to the case, not as a precedent for later cases on the same issues. While attorneys will consult prior decisions when advising clients, judges are rarely bound to follow precedent. For this reason, codes of statutes are usually more extensive and detailed than in common law systems.

In civil law systems, court cases are investigations by the court to see how the facts fit into the already established codes applicable to the situation. The court system is set up so that the jurisdiction of each court is a specific type of code: tax courts, administrative courts, maritime courts, constitutional courts, and so on.

The system is more inquisitorial than adversarial. The process is a series of meetings, hearings, and written communications in which the judge takes testimony. The judge crafts the issues to be decided based on discussions with the parties. Typically, the judge questions the witnesses and can include or exclude any queries submitted by the attorneys when crafting questions. Finally, the judge determines the issues and gathers the evidence before announcing a decision.⁴⁸ Only at the final hearing do the attorneys and parties make arguments to the judge. If there is a jury, its members usually are not drawn from the general public but are selected for their expertise in the particular area in question. While juries of ordinary people are rare in civil law systems, they are increasingly used in serious criminal cases.

These two systems, common law and civil law systems, are the most widely used legal systems in the world. They differ in terms of the weight they give to judicial precedent and their views on the purpose of the trial process.

Religious Systems

In a religious law system, the law relies on religious texts as its primary basis, and the courts interpret the present facts and statutes in light of those religious texts. Many Middle Eastern countries use religious law systems for all or part of their laws.⁴⁹ For example, in Saudi Arabia, the legal system is based on sharia law, derived from the Koran, the Islamic religious text, as well as from the Sunnah and the Hadith.⁵⁰ The legislature enacts statutes, but all are tested against Islamic tenets. Certain religious leaders can overrule any government act, including court decisions, on religious grounds. The legal system includes general and summary sharia courts, with some administrative tribunals for specific topics. Religious law systems do not use juries, and criminal trials do not present defensive evidence to the same extent as in other legal systems. Each judge, a specialist in the religious sharia text, makes their interpretation of the law and is not bound by any precedent.

Israel also uses some religious laws and courts to determine cases.⁵¹ For example, religious courts in Israel include Jewish rabbinical courts, Islamic sharia courts, Druze religious courts, and ecclesiastical courts of the 10 recognized Christian communities. In Israel, these courts are limited to some specific issues of family law. The secular court system decides all other matters.

Customary Systems

A customary law system is a system based on long-standing traditions in a particular community. The traditions have become so ingrained in society that the courts recognize them as enforceable rules. However, it is rare for customary laws to be interpreted and enforced by the government. Instead, select leaders of the group usually implement the customary laws. As a result, customary laws are typically unwritten and revealed only to group members. Today, customary laws are found in closed, isolated communities combined with common or civil law systems, allowing them to exist alongside government systems in a hybrid system.

Andorra, a small country in the Pyrenees bordering Spain and France, relies partly on customary law. In Andorra, sources of customary law include canon law, the ecclesiastical law of the Catholic Church, Castilian law, French law, and Roman law. Andorra was invaded and under the control of other European powers at different times in its history, and the Andorran legal system now reflects elements of each invader’s laws. Today, Andorra is a parliamentary co-principality between the president of France and the Roman Catholic bishop of Catalonia (Urgell). Andorra also has an elected parliament that can enact new laws.⁵²

The island of Guernsey is another example of a customary law system. Though it is one of the Channel Islands off the coast of England, Guernsey is not part of the United Kingdom. Guernsey’s legal system is derived from the medieval power of the monarch, the Duke of Normandy.⁵³ The ancient duchy law of Normandy is an influential source of law in Guernsey. The duchy laws developed in two periods, the Ancienne coutume of 1199–1538 and the Coutume reformée of 1538–1804.⁵⁴ Guernsey’s legal system also has elements of English common law and modern statutory law enacted by the island’s elected legislature. Guernsey enjoys almost complete autonomy over its internal affairs, and the country determines many issues based on ancient customary laws, with elected bailiffs and jurats making decisions.⁵⁵

In the United States, some customary laws may be used in tribal matters on tribal lands recognized by the US government.⁵⁶ However, the US government does exercise some control over tribal legal systems in the United States. There is a growing worldwide movement to recognize tribal autonomy and customary legal systems.⁵⁷ For example, some Maori customary law is now recognized in New Zealand.⁵⁸

Hybrid or Mixed Systems

A hybrid legal system combines parts of more than one approach to create a system unique to the country. Many countries have mixed legal systems incorporating common, civil, religious, and customary law systems.⁵⁹ For example, the US state of Louisiana has a hybrid system. Louisiana uses some common law, but it also utilizes a civil law system for much of its state law and procedures because of its origins as a French territory. Also, on recognized tribal lands, customary laws of the tribe may be used rather than state or federal laws. Another example is the Philippine system, which includes French civil law, US-style common law, sharia law, and Indigenous customary law due to its history.⁶⁰ Many African countries include a parallel tribal or ethnic legal system to adjudicate family law matters.⁶¹

Figure 11.5 This map shows the different types of legal systems present in Africa. (attribution: Copyright Rice University, OpenStax, under CC BY 4.0 license)