In civil and common law countries, lawyers and judges play an important role. In France, civil law was enshrined in the French Civil Code of 1804, also known as the Napoleonic Code. The France exported this legal system to the New World when it moved to Louisiana in 1712. When the French ceded Louisiana to Spain in 1762, the new Spanish governor replaced French civil law with Spanish civil law. The France regained control of the area in 1803 and the United States purchased it only 20 days later. During this short period of French, the French prefect abolished all Spanish courts, but did not reintroduce French law. As a result, the new U.S. governor of Louisiana, William Claiborne, took control of a territory that lacked a legal system. Although Louisiana is generally considered a civil law state, its code is imbued with certain common law characteristics, making it a hybrid of both traditions.

The State Constitution, administrative and criminal law, civil and criminal proceedings and rules of evidence contain all the elements deriving from the principles of the common law. As a result, Louisiana judges work under different administrative regulations than other civil courts. For example, while European judges actively bring facts up in controversy and rarely appoint a jury, Louisiana judges work more like their common law counterparts, assuming the role of a neutral and passive investigator or arbitrator, and leaving the final decision to a jury. Oral pleadings are generally absent in a purely civil action, while Louisiana`s Rules of Procedure and Evidence allow for oral presentations, resulting in trials closer to those of a common law court. Finally, European courts allow almost unlimited disclosure by the defendant in a legal dispute, while Louisiana`s Rules of Procedure and Evidence impose certain restrictions on this discovery. However, some civil law systems do not correspond exactly to this typology. Polish law developed in the 19th century as a mixture of French law and German civil law. After the reunification of Poland in 1918, five legal systems (French Napoleonic Codex of the Duchy of Warsaw, German Civil Code of Western Poland, Austrian ABGB of Southern Poland, Russian Law of Eastern Poland, and Hungarian Law of Spisz and Orawa) were merged into one. Similarly, although originally codified in the Napoleonic tradition, Dutch law was significantly modified under the influence of the dutch indigenous tradition of Romano-Dutch law (which is still in force in its former colonies).

The tradition of Scottish civil law is strongly based on Romano-Dutch law. Swiss law is classified as Germanic, but it was heavily influenced by the Napoleonic tradition, with some indigenous elements also added. A pure common law system is created by the judiciary, since the law comes from the judiciary and not from the law. As a result, a common law system places a strong emphasis on judicial precedents. However, a purely civil system is governed by laws rather than jurisprudence. For the Japanese legal system, from the Meiji era onwards, the European legal systems – especially the civil law of Germany and France – were the main models of imitation. In China, in the last years of the Qing Dynasty, the German Civil Code was introduced, imitating Japan. In addition, it formed the basis of the law of the Republic of China, which is still in force in Taiwan. In addition, Korea, Taiwan and Manchuria, former Japanese colonies, were heavily influenced by the Japanese legal system. The acceptance of Roman law had different characteristics in different countries.

In some of them, its effect was the result of a legislative act; That is, it has become a positive right, while in others it has been accepted by legal theorists thanks to its treatment. Germanist to Napoleonic influence: The Swiss Civil Code is considered to be mainly influenced by the German Civil Code and in part by the French Civil Code. The Civil Code of the Republic of Turkey is a slightly modified version of the Swiss Code adopted in 1926 under the presidency of Mustafa Kemal Atatürk as part of the progressive reforms and secularization of the government. Only legislative acts are considered binding on all. There is little room for judicial law in civil, criminal and commercial courts, although in practice judges tend to follow previous court decisions; Constitutional and administrative courts may repeal laws and regulations and their decisions in such cases are binding on all. A contract that takes up a substantive administrative principle and specifies exactly how it is to be applied will generally be effective. But a modification or repeal of a principle of administrative law may or may not be legally possible – this should be reviewed. For example, it may not be possible to completely deprive a contracting authority of the possibility of unilaterally changing service standards.