Source: JuriGlobe, University of Ottawa
The JuriGlobe research group of the University of Ottawa distinguishes five legal systems worldwide: civil law, common law, Muslim law, customary law and mixed systems. The system a country belongs to shapes every legal aspect of doing business there: how law is made and where you find it, how contracts are drafted and interpreted, how companies are formed and regulated, how property and intellectual property are protected, how employees are hired and dismissed, how disputes are decided and judgments enforced, and what role religion and custom play in all of this. Most countries in Asia, Africa and Latin America have mixed systems, often the result of colonial history combined with religious or customary law.
Civil law system (statute law system)
The civil law system is based on Roman law, which applied first in Rome and later throughout the Roman Empire, and was revived in continental Europe from the Middle Ages onwards. Its main feature: the law is laid down in general, abstract rules that are codified, i.e. collected in systematic codes (in Switzerland: the Civil Code and the Code of Obligations; overview in the Classified Compilation of Federal Law). For this reason, the civil law system is also called the statute law system. Courts apply the codes to the individual case; earlier decisions are important guidance, but not formally binding. Countries with a civil law system also have a written constitution. It is the most widespread system in the world (continental Europe, Latin America, large parts of Asia and Africa; China’s law is also largely codified).
Common law system (case law system)
The common law system originated in England after the Norman conquest and spread with the British Empire: today it applies in the USA (except Louisiana), Canada (except Quebec), Australia, New Zealand and Ireland and, in mixed form combined with religious or customary law, in India, Nigeria, Singapore and many other former British territories. Its main feature: the law develops largely through court decisions. Judges decide the case before them on the basis of earlier decisions, the precedents, which bind lower courts (stare decisis). For this reason, the common law system is also called the case law system. Statutes exist too, and their number is growing, but they are read against the background of the case law. Countries with a common law system usually have a written constitution; the United Kingdom is the exception, its constitution consists of statutes, case law and constitutional conventions.
Muslim law system (Islamic law, Sharia)
Muslim law is derived from the religious sources of Islam, above all the Quran and the Sunnah (the recorded practice of the Prophet, the hadith). «Sharia» denotes the divine law itself; «fiqh» its interpretation by legal scholars, which differs between schools and countries. Only a few states apply Muslim law comprehensively, Saudi Arabia being the clearest example. In most countries with a Muslim majority it governs family and inheritance law, while commercial law follows civil or common law models (mixed systems, e.g. Egypt, Malaysia, Indonesia, Pakistan). For business, the most visible effect is Islamic finance: the prohibition of interest (riba) and of excessive uncertainty (gharar) has produced its own financial products, such as sukuk instead of bonds. It is a market of over USD 4 trillion (IFSB, 2026), led by Iran, Saudi Arabia and Malaysia, which also attracts Western banks.
Customary law system
Customary law is unwritten law: rules that have developed through long practice and are accepted as binding by the community concerned. It exists in every legal system as a subsidiary source. In Switzerland, for example, the Civil Code instructs the courts to apply customary law where the statute is silent (Art. 1 Swiss Civil Code). Legal systems based mainly on customary law are rare today; JuriGlobe lists only a few small jurisdictions. In many countries of Africa and the Pacific, however, customary law remains a major source of law alongside state law, in particular for land, family and inheritance matters, which businesses must take into account, for instance when acquiring land.
Mixed legal systems
As the map shows, only part of the world belongs to a single system. In many countries two or more systems apply side by side or are combined: mixed legal systems. Typical patterns are common law or civil law inherited from a colonial power, combined with religious law (mostly Muslim law) for family matters and with customary law for land and community matters. Examples (JuriGlobe index): India (common law, Muslim law, customary law), Indonesia (civil law, Muslim law, customary law), South Africa (civil law and common law), Scotland and Quebec (civil law and common law within a common law state). China, Japan and South Korea are classified as civil law combined with customary law. For a business, a mixed system means that the applicable rules may depend on the subject matter and on the parties involved.
Civil law and common law are converging
The two large systems are moving towards each other. In civil law countries, case law plays a growing role: where statutes are concise and general, as in Switzerland, the courts have a wide margin of interpretation, and their decisions are increasingly cited. In common law countries, more and more law is codified, partly because international agreements must be implemented by statute (e.g. the US Copyright Act, amended in 1988 and 1998 to implement the Berne Convention and the WIPO treaties).
Impact of the legal system on legal work
The legal system has a direct influence on the work of lawyers. In a common law country, the amount of research is enormous, because it is not primarily the codified law that is applied, but the cases decided by the courts. This is true, for example, of lawyers in the USA. In Switzerland, a civil law country, lawyers primarily apply the codified law and then add the relevant court decisions. In practice, this is a completely different process and much less time-consuming. However, the two systems are becoming more similar here too: digitalisation has made research much easier for US lawyers, and it has led Swiss lawyers to cite more court decisions, today also decisions of cantonal courts, not only of the Federal Supreme Court. For a business, this matters: legal work in a common law country takes longer and costs more, and you should expect that when you plan a market entry.
Check your jurisdiction
Ask a chatbot of your choice (Claude, ChatGPT & Co.): «Which legal system does [my country] belong to according to JuriGlobe (University of Ottawa): civil law, common law, Muslim law, customary law or mixed? If mixed, which components, and which areas of law do they govern?»
Validate the answer against the original source: JuriGlobe, alphabetical index of countries.
In class: we place the class on the map and compare what your systems mean for finding the law and for doing business in your country.