Codification (law)

Codification is the process of gathering and restating a jurisdiction’s laws by subject, resulting in a legal code—a book of law. It is a hallmark of most civil law systems. In common law systems, such as English law, codification means turning judge-made law or uncodified legislative statutes into codified statute law.

The earliest known surviving civil code is the Code of Ur-Nammu from ancient Sumer, compiled around 2050–1230 BC. About three centuries later, the Babylonian king Hammurabi enacted his own set of laws. Important codifications appeared in ancient Rome, including the Lex Duodecim Tabularum and later the Corpus Juris Civilis, though these were exceptions since Roman laws were mostly uncodified for much of antiquity. The first permanent system of codified laws emerged in imperial China with the Tang Code of AD 624, which became the basis for the Chinese criminal code. It was eventually replaced by the Great Qing Legal Code, abolished in 1912 after the Xinhai Revolution and the founding of the Republic of China. The new Republic’s laws were inspired by the German Bürgerliches Gesetzbuch. A highly influential European example was the French Napoleonic Code of 1804. Upon confederation, the Iroquois created constitutional wampum, each component symbolizing one of the many laws within their 117 articles. The union of the five original nations occurred in 1142, and its unification narrative formed the basis for Iroquois laws. Religious legal systems include Judaism’s halakha and Islam’s sharia. The use of civil codes in sharia began with the Ottoman Empire in the 19th century. American legal scholar Noah Feldman has argued that the Ottoman codification of sharia reduced the power of the religious scholarly class, upsetting the balance of powers and the traditional uncodified constitution of Islamic societies, leading to autocrats unconstrained by the rule of law in the Muslim world.

Civil law jurisdictions rely on codification by definition. Notable early examples were the Statutes of Lithuania in the 16th century. The codification movement gained momentum during the Enlightenment and was implemented in several European countries in the late 18th century, but it became widespread only after the French Napoleonic Code of 1804, which heavily influenced many other legal systems. That code served as a primary model across Continental Europe and Latin America, abolishing feudal legal structures in favor of uniform civil laws.

Common law has been codified in many jurisdictions and areas of law. Examples include criminal codes in many places, the California Civil Code, and the Consolidated Laws of New York. In England and Wales, Sir Mackenzie Chalmers drafted the Bills of Exchange Act 1882, the Sale of Goods Act 1893, and the Marine Insurance Act 1906, all codifying existing common law principles. The Sale of Goods Act was repealed and re-enacted by the Sale of Goods Act 1979, revealing how sound the 1893 original had been. The Marine Insurance Act, mildly amended, has been notably successful and adopted verbatim in many common law jurisdictions. Most of England’s criminal laws have been codified, partly for precision and certainty in prosecution. However, large areas of common law, such as contract and tort, remain largely untouched. In the last 80 years, statutes have addressed immediate problems, like the Law Reform (Frustrated Contracts) Act 1943 and the Contracts (Rights of Third Parties) Act 1999, but no progress has been made on adopting Harvey McGregor’s Contract Code from 1993, even though the Law Commission and the Scots Law Commission asked him to propose comprehensive codification and unification of contract law for England and Scotland. Codification in tort law has been piecemeal, with a rare example being the Law Reform (Contributory Negligence) Act 1945. Consolidation bills are routinely passed to organize the law.

Ireland’s law evolved from English law, the main difference being its Constitution as a single document. The unofficial “popular edition” of the Constitution is regularly updated for amendments, while the official text enrolled in the Supreme Court in 1938 has been replaced five times: in 1942, 1980, 1989, 1999, and 2019. As in England, subordinate laws are not officially codified, though consolidation bills have restated law in many areas. Since 2006, the Law Reform Commission has published semi-official “revised” editions of Acts of the Oireachtas, accounting for textual and other amendments. Finance Acts are excluded from this program. Private companies produce unofficial consolidated versions of these and other commercially important pre-2005 laws. An official advisory committee between 2006 and 2010 produced a Draft Criminal Code.

In the United States, a critique of the inherited English common law tradition and an argument for systematic codification was championed by the United Irish exiles William Sampson.