Japan

• The Constitution of 1947, the highest law
• The main codes: the Civil Code, the Commercial Code, the Criminal Code and the two procedure codes
• Statutes passed by the National Diet (the parliament)
• Court decisions, especially from the Supreme Court, which guide lower courts in practice

• The Supreme Court at the top
• High Courts (several regional ones, plus a specialised Intellectual Property High Court)
• District Courts, Family Courts and Summary Courts at the first level

A law degree and a national bar examination, then a period of training at the Legal Training and Research Institute run by the Supreme Court. Future judges, prosecutors and attorneys all train there together.

• Future judges, prosecutors and attorneys train together, which is unusual.
• Since 2009, ordinary citizens sit with professional judges as lay judges in serious criminal cases.
• Japan has relatively few lawyers and few lawsuits, and conciliation and mediation are very common.
• Japan's codes have a German structure, so German legal ideas are a good way to understand Japanese private law.

Germany, France, China, Bulgaria, Russia

The University of Ottawa’s JuriGlobe database lists Japan as: Civil law, Customary. It names the systems in order of importance.

The map colours a country by the first-named system, and shows both civil-law and common-law countries as “mixed”. It is a simplification, and real systems are rarely pure.

Albania, Algeria, Angola, Argentina, Armenia, Austria, Azerbaijan, Belarus, Belgium, Benin, Bolivia, Bosnia and Herzegovina, Brazil, Bulgaria.

• Courts in Japan (Supreme Court of Japan)
• Legal Training and Research Institute of Japan
• Japanese Law Translation (Ministry of Justice)

Sources last reviewed: October 2026.