extradition (ĕkstrədĬsh´ən), delivery of a person, suspected or convicted of a crime, by the state where he has taken refuge to the state that asserts jurisdiction over him. Its purpose is to prevent criminals who flee a country from escaping punishment. Extradition first became a common policy in the 19th cent. International law does not recognize extradition as an obligation in the absence of a treaty, and although a state may, as a matter of courtesy, refuse asylum to a fugitive and honor a request for extradition, virtually all extradition takes place under the authority of bilateral treaties. The provisions of each nation's treaties may differ greatly from those of another, and it should be noted that some treaties are formulated so that a nation is not obligated to extradite. Extradition treaties agreed to by the United States require evidence that would show the accused to have violated the laws of both the United States and the demanding country. Moreover extradition can occur only for an offense that has been named in the treaty. In common with many other nations, the United States will not surrender a fugitive wanted for a political crime. American treaties generally provide that U.S. nationals will be surrendered for trial in a foreign country. In contrast to the United States and Great Britain, most nations of the European Continent will surrender a fugitive upon simple demand and will try their own nationals domestically for crimes committed abroad. The U.S. Congress, pursuant to Article 4, Section 2, of the U.S. Constitution, has established a uniform law of extradition between the states, known as interstate rendition. This law provides that any person properly charged is subject to extradition regardless of the nature of the crime. Although the states normally comply with extradition demands, the Supreme Court has held that they have the right to refuse compliance.