Jurisdiction refers to those who have responsibility, authority or control of a particular area. Local and Federal jurisdictions are determined by which law has been violated. If a federal crime involving a federal law has been committed, federal authorities have jurisdiction. In the case of local crimes, local authorities have jurisdiction. This can be somewhat complicated because some crimes may violate laws of both federal and local jurisdiction. There are also federal laws that differ from state or local law. It is often difficult to determine jurisdiction in many cases.