treaty provision, the United States does not have a general policy of refusing extradition if the crime at issue could not be prosecuted in U.S. courts based on statutes of limitation. However, some foreign governments have constitutional or national laws that limit their authority to extradite if the local statute of limitations that would apply to such an offense if committed in that country has expired.
Other Reasons that Extradition is Denied
-- List v. Dual Criminality Treaties.
Extradition treaties are designed to engage the complex and expensive international process only with respect to serious offenses. In older U.S. treaties that were negotiated before the late 1970’s, this was accomplished by agreeing to a list of offenses that would be covered. For countries still covered by such “list” treaties, a request for extradition for a crime not included would be rejected. In newer treaties concluded in the last 20-30 years, this list approach has been replaced by the concept of “dual criminality,” usually providing that offenses covered by the treaty include all those made punishable under the laws of both Parties by imprisonment or other form of detention for more than one year, or by a more severe penalty (such as capital punishment). Such a formulation obviates the need to renegotiate the treaty to provide coverage for new offenses, strikingly exemplified by the currently evolving area of cyber-crime. Indeed, to avoid having the dual criminality analysis applied too narrowly, most treaties provide further guidance, including that an offense is extraditable whether or not the laws in the two countries place the offense within the same category or describe it by the same terminology. A major goal in our current ambitious treaty negotiating program is to negotiate new, modern treaties that eliminate the “list” approach in favor of dual criminality treaties.
-- Sufficiency of Evidence.
Extradition treaties, as well as relevant domestic law, require that a certain quality and character of evidence be presented before extradition will be ordered for persons not yet convicted. In extradition proceedings in the United States, sufficient evidence must be presented to satisfy a court that there is “probable cause” to believe that the crime for which extradition is requested has been committed, and that the fugitive committed it. The laws of several of our treaty partners have similar thresholds analogous to “probable cause”; a few require what amounts to a higher “prima facie” standard of enough evidence to sustain a judgment of conviction based on the evidence in the extradition request. Some of our other treaty partners do not require evidence sufficient to establish what we would deem probable cause in order to extradite fugitives to the United States.
-- Additional Exceptions to the Obligation to Extradite.