Years ago, a wanted criminal was generally home free if he or she could make it out of the country where he or she was wanted and into another country. Now, however, there are many international extradition treaties that compel one country to surrender a criminal suspect or convicted criminal back to the country from which he or she fled. Under the general principles of international law, each country has sovereignty, meaning it may make, interpret, and enforce its own laws, and is not obligated to abide by the laws of any other country. As a result, the only way to secure cooperation between countries in situations where a suspect or convict has fled from one country to another is through international extradition treaties.
Over the years, countries have entered into extradition treaties with other countries across the world that have created an elaborate labyrinth of conditions and agreements regarding the process of extraditing a person from one country to another. No country is under an obligation to extradite under any circumstance absent a voluntary agreement. Therefore, all extraditions are done by agreements formalized in extradition treaties.
Although the terms of extradition treaties will vary depending on the countries involved, there are some common reasons why a country will refuse to agree to extradite. Some countries require that the crime for which the person is charged have a counterpart within the country where the person has fled. The prerequisite is not usually that the countries have an equivalent crime, but only that the country being asked to extradite consider the crime for which the person has been charged to be a crime of some sort.
Many countries will also refuse to extradite for political crimes or for crimes in which the person may face torture or the death penalty. The majority of legal systems throughout the world have abolished the use of capital punishment and, therefore, will not allow an extradition to a country that does allow capital punishment. Canada, Mexico, and many European countries, for example, refuse to extradite to countries that impose the death penalty. In some cases, however, extradition treaties allow extradition to capital punishment jurisdictions, but only when assurance has been given that the death penalty will not be sought.
Countries may also refuse to extradite their own citizens, or in cases where they also have jurisdiction over the crime. Extradition requests do not present themselves only in cases where a citizen has fled his or her own country of origin. In some cases, a foreign national commits a crime in a foreign country and then returns to his or her country of citizenship. Japan, France, and the Russian Federation, for example, refuse to extradite their own citizens.