There are three major forces that regulate and enforce immigration law: immigration courts, Immigration and Customs Enforcement (ICE), and the U.S. Center for Immigration Services (USCIS). Together these forces oversee nearly all aspects of immigration law from the apprehension and deportation of illegal aliens, to the approval of lawful permanent residents and general naturalization requirements.
ICE serves as the main enforcement arm of the U.S. immigration system. ICE is the primary force behind detainments, deportations, and voluntary removal supervision. The USCIS is the administrative force behind U.S. immigration law. The USCIS processes most immigration-related forms and documents and monitors the status of legal immigrants and temporary visitors to the United States. Finally, the immigration courts are special administrative courts designed to oversee the processes of asylum, deportation, and immigration appeals. It is strongly recommended that if you must appear before an immigration court, you should hire an immigration attorney.