Defining Customary Law

Customary law is a set of laws based on the traditions, customs, or norms of a local community. It is applied in many countries around the world, often in conjunction with civil, common, and religious legal systems. The content and features of customary law regimes vary by country or region and may evolve over time, in keeping with changes in local customs. In countries with weak formal justice systems, the use of customary law is more prevalent. 

Customary law may be implemented by national judiciaries, but in many countries it is applied through traditional, often informal, justice systems. These traditional systems, rooted in family and community structures, resolve disputes at the local or regional level. Some are government-sanctioned, others are not officially recognized. 


As with any legal system, elements of customary law have come under scrutiny. For example, the institutionalization of customary law has been challenged when it reflects colonial influence rather than indigenous mores. In other cases, customary law practices have been criticized for failing to comport with international human rights norms. Many national governments have taken note, instituting measures to address these concerns. For a more in-depth discussion of this issue, see the sources included here.


How is Customary Law Different?

Customary law is often—but not always—unwritten. It is based on long-standing traditions, customs, and rules that a community accepts as binding. Customary law is often administered at the local level in accordance with tradition and dispute resolution mechanisms. However, in some countries, it is enforced within the modern court system. Some national court systems require that customary law principles be proven as a question of fact, whereas others permit proof through written documents or prior legal decisions. Many countries that formally recognize customary law require that its enforcement not conflict with any statute, public policy, or enumerated values and principles.


Examples of Customary Laws in Practice

Outline of United States

The United States

Within the United States, the customs and traditions of Native American tribes are binding and enforceable in tribal courts. Native American tribal courts frequently cite to customary law in written opinions. The Navajo courts, for example, have recognized a customary law right to notice, as well as a right to indigent representation and effective counsel during a trial.


South Korea

In South Korea, many elements of custom are considered in the application of some aspects of civil, commercial, criminal, and family law. Article 1 of South Korea’s Civil Code notes that custom is a source of law. Article 185 of the Civil Code states that property rights can be created through customary law. One example of this is the “superficiary” right to own a building or tree separately from the ownership of the land on which a structure or tree stands. This right is derived from custom, and Korean courts have determined that registration of the right is not always required for enforcement.

Outline of South Korea
Outline of Zambia


In Zambia, traditional courts administered by local chiefs administer justice for criminal cases at the local level. Zambia’s Lands Act of 1995 empowers local chiefs to allot land to their subjects. In practice, this means they grant the right for occupation and use of land and can impose conditions on certain uses (e.g., prohibiting cultivation of land or preventing animals from grazing in certain areas).



In Andorra, courts apply the customary laws of Andorra and Catalonia in addition to its civil codes. Many of Andorra’s customs are compiled in books.

Outline of Andorra
Outline of Jordan


In Jordan, the legal system is primarily a mixture of civil and Islamic law. It defers to tribal custom for tribal groups—known as the Bedouin—for some aspects of criminal and family law. Jordan’s state courts and police forces recognize the customs and traditions of the Bedouin tribes for criminal and family matters. For example, in a murder case, a tribal mediation process takes place to address the issue of revenge. Under Bedouin tribal law, when a murder takes place, the members of the victim’s family have a right to avenge the victim’s death by murdering a member of the perpetrator’s family. The state police in the village intercede to secure a truce, and tribal leaders initiate a mediation process to achieve a peace agreement involving monetary compensation to the victim’s family. This process usually takes place in addition to criminal proceedings initiated by the government against the perpetrator.



In Jersey, an island near the coast of northwest France, custom is a source of law and is used in many civil cases, including contract and tort cases. The statute of limitations period in Jersey for many types of commercial disputes is usually derived from a mixture of both customary law and case law.

Outline of Jersey