Common law vs civil law: the world's two legal traditions

Common law vs civil law is the main divide among the world's legal systems. Common law, from England, treats judges' past decisions as law that later courts must follow. Civil law, from continental Europe, starts from comprehensive written codes descended from Roman law, which judges apply. Civil law is the more widespread, used in some form in about 150 countries; common law runs through England's former colonies, including the United States, India and Australia.

In short

• In common law, precedent is a source of law; in civil law, the code is, and precedent guides without formally binding.
• Common law trials are adversarial contests between lawyers; civil law procedure gives the judge a more active, investigating role.
• "Civil law" also means non-criminal law, which is a different thing, and most countries now mix features of both traditions.

Not legal advice

This note describes the two traditions in general terms. Every country's system differs in detail, and nothing here is advice about any case.

Where did the two traditions come from?

Common law grew in England after the Norman Conquest of 1066. Under Henry II, who ruled from 1154 to 1189, royal judges traveled the country hearing cases, and the rules they applied were called common because they were the same across the realm, replacing a patchwork of local customs. Their decisions were recorded, and over the following centuries the habit of following them hardened into a principle, stare decisis, "to stand by things decided": a court follows earlier rulings on the same question. The strict rule that a higher court's precedent binds lower courts was settled only in the 19th century. Law was made case by case, long before Parliament passed much legislation.

Civil law goes back to Rome. In 529 to 534, the Byzantine emperor Justinian had the whole of Roman law collected into one body, later called the Corpus Juris Civilis. Rediscovered in the late 11th century, it was taught at the new university in Bologna and spread across Europe's universities as a common learned law. Modern civil law took its form from codes: France's Civil Code of 1804, known as the Napoleonic Code, and Germany's Civil Code, the BGB, in force from 1900. The French code spread with Napoleon's armies and later by imitation to Latin America and much of the Arab world; the German code shaped Japan, South Korea and others. Its distant ancestor is the law of the Roman Empire.

How do common law and civil law differ?

The differences are of emphasis, not of kind, but they are real:

	Common law	Civil law
Main source of law	Statutes and judges' decisions, with precedent binding	Codes and statutes; decisions guide but don't formally bind
Style of rules	Narrow rules built up from many cases	Broad principles set out in advance
Judges	Usually appointed from experienced lawyers	Usually career judges, trained for the bench after law school
Role of the judge at trial	Referee between two sides who present the evidence	Directs the inquiry, questions witnesses, appoints experts
Trial	Oral, with cross-examination; juries common in criminal cases	More written, built around a case file; juries rare
Court opinions	Long, reasoned, often with dissents	In France, short and formal; in Germany, longer
Leading legal writers	Influential	Very influential: scholars' commentary shapes how codes are read

A telling detail: Article 5 of the French Civil Code forbids judges to rule "by way of general and regulatory provision" on cases before them. A French judge decides the dispute, not the law for everyone. In practice, a consistent line of decisions from France's highest court, the jurisprudence constante, carries great weight all the same.

How would one dispute play out in each?

Take a real case, step by step. In August 1928, May Donoghue drank a bottle of ginger beer a friend bought her in a café in Paisley, Scotland. A decomposed snail, she said, was in the bottle, and she fell ill. She couldn't sue the café, because she had no contract with it, so she sued the manufacturer, David Stevenson.

The common law route. Her lawyers had to find a rule in earlier cases, and the cases were against her: a maker owed a duty of care to someone it had no contract with only in narrow situations, such as goods known to be dangerous. So the question became whether the courts would recognize a new duty. On 26 May 1932, the House of Lords, then the top court, held by 3 to 2 that they would. Lord Atkin wrote: "You must take reasonable care to avoid acts or omissions which you can reasonably foresee would be likely to injure your neighbour." That sentence became a precedent that bound later courts, and it founded the modern law of negligence across the common law world. The rule did not exist until a court made it, deciding one case. (Scotland's system is mixed, but on this point the judges treated Scots and English law as the same.)

The civil law route. In France the same question would start with the code, not with old cases. Since 1804 the Civil Code has said, in what is now Article 1240, that "any act of a person which causes harm to another obliges the one by whose fault it occurred to make reparation", and the next article extends this to negligence. No contract is needed. The judge's questions are whether the maker was at fault, whether there was harm, and whether one caused the other. The court might appoint an expert to examine the bottle, work largely from written submissions, and give a short judgment citing the articles. The general rule was there in advance; the court applied it.

The two routes now meet. Since a 1985 European directive, both the United Kingdom and France have had specific laws making producers liable for defective products without proof of fault. Each tradition reached a similar answer: a common law court through a famous case, a civil law code through a general principle, and both, later, through legislation.

Which countries use which system?

According to the University of Ottawa's JuriGlobe classification, common law systems include England and Wales, Ireland, the United States, most of Canada, Australia and New Zealand, along with many former British colonies, several of which mix it with religious or customary law. Civil law systems cover continental Europe, Russia and Latin America, and much of Africa and Asia, often blended with customary law: JuriGlobe lists both Japan and China as civil law mixed with custom, and China's system is also shaped by its socialist legal tradition.

Mixed systems combine the two. Scotland pairs Roman-derived principles with its own case law. South Africa and Sri Lanka use Roman-Dutch law alongside English-style courts. Inside common law countries there are civil law islands: Louisiana keeps a civil code for private law, a legacy of French and Spanish rule, and so does Quebec within Canada. Other countries add religious law, such as Islamic family law, or customary law, to either tradition.

Why does "civil law" have two meanings?

Because the same phrase names two different things. As a legal tradition, "civil law" is the code-based family described above, from the Latin ius civile, the law of Roman citizens. Inside any system, "civil law" also means non-criminal law: disputes between private parties over contracts, property, family and harm, as opposed to crimes prosecuted by the state. So the United States, a common law country, has civil courts and civil cases, and France, a civil law country, has criminal courts. The context tells which is meant: "a civil law country" is about tradition; "a civil lawsuit" is about the kind of case. The divisions of law are set out in what law is.

Are the two systems becoming more alike?

Yes, from both directions. Common law countries now legislate heavily, so judges in England or the United States spend much of their time interpreting statutes rather than making rules. Civil law courts publish more reasoning and lean on their own past decisions, and constitutional courts in Germany, Spain and elsewhere make rulings with effects much like precedent. The US Supreme Court remains the clearest example of judges' decisions as law, and the medieval English roots of that idea run back past the Magna Carta.

Check yourself

• Without looking back, explain how Donoghue v Stevenson would have been argued in a common law court and in a French one.
• What does stare decisis mean, and why don't civil law courts formally follow it?
• Why can a common law country have civil courts?

Sources

• Common law — Wikipedia
• Civil law (legal system) — Wikipedia
• Code civil, article 1240 — Légifrance, Government of France
• Donoghue v Stevenson — Wikipedia
• Alphabetical index of the political entities and corresponding legal systems — JuriGlobe, University of Ottawa
• Stare decisis — Legal Information Institute, Cornell Law School