Different countries have different legal systems. You may have heard the terms “common law” and “civil law” used before to describe the legal systems of different countries. But what exactly is common law? What is civil law? How do these legal systems work?
“Common law” refers to those legal systems originally based on English law, where judges play a large rule in shaping the law through deciding cases and creating precedent. Modern common law countries include the United States, Canada, Australia, and the United Kingdom. “Civil law,” on the other hand, refers to those countries where the law is based primarily on written legal codes instead of judicial decisions.
How Does Common Law Work?
Common law is also sometimes called “judge-made” law due to the significant role that judges play in shaping the law. A common law system operates on the principal that like cases should be treated alike. Therefore, a judge in a common law system will look to similar cases decided in the past and apply the principles outlined in those cases to the present case. These past cases are called “precedent”.
Over time, as the judges in a common law country develop more and more precedent after deciding numerous legal issues, these precedents themselves form a body of law. If you ever hear lawyers in the United States or other common law countries talk about “case law,” this is precisely what they’re talking about – court cases from the past that control how a judge should decide the present case.
Typically, a common law country will have a hierarchical court system, whereby higher-ranked courts will hear appeals from lower-ranked courts. For example, in the United States’ federal court system, there are District Courts, Circuit Courts, and the United States Supreme Court.
The Circuit Courts hear appeals from the District Courts, and the Supreme Court hears appeals from the Circuit Courts. The precedents created by the Circuit Courts are binding on all of the District Courts that are underneath them, and the precedents created by the Supreme Court are binding on the entire country.
Of course, not all of the law in a common law system is created by judges deciding cases. In the United States, Congress, as well as state legislatures, still pass written codes of law – called statutes. However, in a common law system, judges will typically have the final say on the interpretation of these statutes.
Additionally, within common law legal systems, bodies of law that are solely derived from judge-made precedent are confusingly referred to as “common law”. Areas of law governed by statutes written by legislature are referred to as statutory law. For example, in the United States, tort law and contract law are for the most part not delineated by written legal codes, but rather by judge-made precedent, and these subject areas are referred to as “common law” by lawyers, judges, and legal scholars.
Another typical feature of common law legal systems is an “adversarial” system of justice. In an adversarial system, the judge does not take an active role in deciding a case. Instead, evidence and legal arguments are presented by the two opposing parties, often with the aid of lawyers. Then, the judge or sometimes a jury will rule upon the arguments and evidence and render a decision. This is why in common law legal systems such as the United States, you will see the title of a court case with a “v.” in the middle of it, designating the two adversarial parties to a case.
How Did Common Law Originate?
The common law system originated in England during the Middle Ages. When the Anglo-Saxons took control of England following the collapse of the Western Roman Empire, they brought with them their native Anglo-Saxon law. However, in 1066, England was conquered by the Duke of Normandy, William the Conqueror. William, his descendants, and his nobles were not Anglo-Saxons – they spoke Norman French instead of Old English, and their legal customs differed greatly from their Anglo-Saxon subjects. William’s new nobility needed a way to maintain law and order while still upholding the law of his Anglo-Saxon predecessors.
William’s great-grandson, King Henry II, would go on to develop the curia regis – the King’s Court. The judges of the King’s Court would travel throughout the country to hear controversies around England. In doing so, the judges would use local Anglo-Saxon customs in deciding the cases. Over time, the decisions of these judges formed a body of law common to the whole of England – the “common” law.
What Countries Use Common Law Today?
Today, common law legal systems are found in the United Kingdom and almost all of its former colonies. As the British Empire expanded, it imposed its own legal system on the colonies it came to possess. This included what is today the United States, Canada, Australia, and New Zealand.
Although most colonies of the British Empire would eventually become independent, they retained legal systems based upon the common law system originating in England. These legal systems are of course much more evolved than that which developed in England during the Middle Ages, but they nonetheless follow the same basic principles: like cases should be treated alike, and the precedents set by previous cases should usually be followed.
How Does Civil Law Work?
By contrast, a civil law system is a legal system whereby the law is primarily established through written legal codes. Although judges in a civil law system may have some power to interpret the law, their decisions usually do not carry the same weight as they do in a common law system. Because judge-made law does not form a backbone of civil law systems, their legal codes tend to be much more exhaustive and attempt to cover the whole body of law for a country.
Additionally, civil law systems often, but not always, utilize an “inquisitorial” system of deciding cases. In an inquisitorial system, the judge is not necessarily impartial, and takes a much more active role in investigating a particular case. They will often perform the roles that lawyers would play in common law legal systems, asking questions of witnesses in an attempt to determine the truth. In common law systems, judges are impartial and decide a particular case based upon the evidence and arguments presented by two opposing sides.
However, it is important to note that the phrase “civil law” can also have a specialized meaning within a common law legal system. When used in this sense, the phrase civil law essentially means private law – law dealing with the rights and responsibilities of private citizens in relation to each other, such as the law of contracts. Typically, this use of the phrase “civil law” is used in contrast to “public law” – law dealing with society as a whole, such as criminal law.
How Did Civil Law Originate?
Although legal codes can date back to the Code of Hammurabi (c. 1700 BCE) and before, civil law ultimately has its roots in Roman law. One of the earliest legal codes in ancient Rome was the Law of the Twelve Tables. Written at the very beginning of the Roman Republic in the 5th century BCE, the Twelve Tables was a comprehensive legal code, laying out the rights and duties of Roman citizens in all areas of the law.
One of the most influential civil legal codes was that composed by Byzantine Emperor Justinian I between 529 and 534, known as Corpus Juris Civilis or the “Code of Justinian”. The Code of Justinian was not an entirely new set of laws, but rather a compilation of many previously enacted imperial laws of the Roman and later Byzantine Empire. The Code of Justinian, though designed for a 6th century world, nonetheless had a substantial influence on civil law systems to the modern day.
Another important civil law code is the Napoleonic Code, named after French Emperor Napoleon and codified in 1804. The Napoleonic Code was itself inspired by the Code of Justinian, and spread throughout Europe with Napoleon’s conquests in the Napoleonic Wars spread this legal code throughout continental Europe. The Napoleonic Code is still in force in France today.
What Countries Use Civil Law Today?
The civil law system is the most widely used type of legal system in the world today Almost all countries in Europe, excluding the United Kingdom and Ireland, use some form of a civil law system as their legal system today, including Albania, Armenia, Austria, Belgium, Croatia, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary Ireland, Italy, Latvia, Lithuania, the Netherlands, Norway, Poland, Portugal, Romania, Russia, Serbia, Slovakia, Spain, Sweden, and Switzerland.
However, though most civil law systems have some basis in Roman law, the Code of Justinian, or the Napoleonic Code, each civil law system is unique. For example, the Scandinavian nations (Norway, Denmark, Sweden, Finland, and Iceland) all have civil law systems, they are nonetheless greatly influenced by medieval Scandinavian law codes based on custom and tradition, not altogether very different from the Anglo-Saxon law mentioned previously. Additionally, though technically civil law countries, the Scandinavian nations tend to place somewhat more emphasis on the decisions of judges, though not as much as in common law systems.
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Wesley M. Bernhardt is an attorney, writer, and former prosecutor. He graduated with a Juris Doctor cum laude from Washington University School of Law in 2019. Thereafter, he spent more than two years as a prosecutor in one of America’s largest prosecutor’s offices.