Courts of Indian Offenses, known as CFR courts, perform a judicial function for tribes who do not have an independent justice system. CFR courts must adhere to tribal customs unless they conflict with a federal regulation that has not been superseded by tribal laws. These courts hold civil jurisdiction over matters arising on tribal lands in which tribal members are defendants, including matters that involve non-Native Americans. Civil jurisdiction also arises in a CFR court if the defendant consents. CFR courts hold criminal jurisdiction over misdemeanors involving Native Americans on tribal lands.