Traditionally,some minimal dollar amounts had to be in controversy in some types ofcases before the trial courts would hear them,but such amounts have been waived ifthe case falls into one ofseveral general cate-gories.For example,an alleged viola-tion ofa civil rights law,such as the Voting Rights Act of1965,must be
heard by the federal rather than the state judiciary.Other types of cases in this category are patent and copyright claims,passport and naturalization proceedings,admiralty and maritime disputes,and violations ofthe U.S.postal laws.
Another broad category of cases over which the U.S.trial courts exer-cise general original jurisdiction in-cludes what are known as diversity of citizenship disputes.These are dis-putes between parties from different states or between an American citizen and a foreign country or citizen.
Federal district courts also have jurisdiction over petitions from con-victed prisoners who contend that their incarceration (or perhaps their denial ofparole) is in violation of their federally protected rights.In the vast majority ofthese cases prisoners ask for a writ ofhabeas corpus (Latin for you should have the body),an order issued by a judge to determine whether a person has been lawfully imprisoned or detained.The judge would demand that the prison authorities either justify the detention or release the petitioner.Prisoners convicted in a state court must argue that a federally protected right was violated for example,the right to be represented by counsel at trial. Otherwise,the federal courts would have no jurisdiction.Federal prisoners have a somewhat wider range for theirappeals since all their rights and options are within the scope of the U.S.Constitution.
Finally,the district courts have the authority to hear any other cases that Congress may validly prescribe by law.