Legal jurisdictions

The contemporary legal systems of the world are generally based on one of four basic systems: civil law, common law, statutory law, religious law or combinations of these. However, the legal system of each country is shaped by its unique history and so incorporates individual variations.

Both Civil (also known as Roman) and Common law systems can be considered the most widespread in the world, Civil law because it is the most widespread by landmass, and Common law because it is employed by the greatest number of people.

Common law and equity are systems of law whose sources are the decisions in cases by judges. Alongside, every system will have a legislature that passes new laws and statutes. The relationships between statutes and judicial decisions can be complex. In some jurisdictions, such statutes may overrule judicial decisions or codify the topic covered by several contradictory or ambiguous decisions. In some jurisdictions, judicial decisions may decide whether the jurisdiction's constitution allowed a particular statute or statutory provision to be made or what meaning is contained within the statutory provisions. Statutes were allowed to be made by the government. Common law developed in England, influenced by Anglo-Saxon law and to a much lesser extent by the Norman conquest of England, which introduced legal concepts from Norman law, which, in turn, had its origins in Salic law. Common law was later inherited by the Commonwealth of Nations, and almost every former colony of the British Empire has adopted it (Malta being an exception). The doctrine of stare decisis, also known as case law or precedent by courts, is the major difference to codified civil law systems.

Common law is currently in practice in Ireland, most of the United Kingdom (England and Wales and Northern Ireland), Australia, New Zealand, Bangladesh, India (excluding Goa),Pakistan, South Africa, Canada (excluding Quebec), Hong Kong, the United States (on a state level excluding Louisiana), and many other places. In addition to these countries, several others have adapted the common law system into a mixed system. For example, Nigeria operates largely on a common law system, but incorporates religious law.

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