Legal systems around the world vary greatly, but they usually follow either civil law or common law. The difference between these systems lies in the actual source of law.
Common law is generally referred to as the legal system of Anglo-American countries, which is based on case law, as opposed to civil law, which is based on codified law.
In common law, past legal precedents or judicial rulings are used to decide cases at hand. This allowes judges to pro-actively contribute to rules. For example, the elements needed to prove the crime of murder are contained in case law rather than defined by statute. In order to maintain consistency, courts abide by precedents set by higher courts examining the same issue.
In common law, the judge often acts as a referee, as two lawyers argue their side of the case. Generally, the judge, and sometimes a jury, listen to both sides to come to a conclusion about the case.
The United States, Canada, England, India, and Australia are generally considered common law countries. Because they were all once subjects or colonies of Great Britain, they have often retained the tradition of common law.
Under civil law, on the other hand, codified statutes and ordinances rule the land. In these systems, codes and statutes are designed to cover all eventualities, and judges have a more limited role of applying the law to the case in hand. Past judgments are no more than general guides.
In civil law countries, the judge is usually the main investigator, and the lawyer's role is to advise a client on legal proceedings, write legal pleadings, and help provide favorable evidence to the investigative judge.
Civil law countries include for example almost all of Europe (including Germany, France, and Spain), China, and Japan.
South Africa, Namibia, Botswana, and Zimbabwe are bijuridical, which means that they follow a combination of both legal systems.
