<P> A State Supreme Court, other than of its own accord, is bound only by the U.S. Supreme Court's interpretation of federal law, but is not bound by interpretation of federal law by the federal court of appeals for the federal circuit in which the state is included, or even the federal district courts located in the state, a result of the dual sovereigns concept . Conversely, a federal district court hearing a matter involving only a question of state law (usually through diversity jurisdiction) must apply the substantive law of the state in which the court sits, a result of the application of the Erie Doctrine; however, at the same time, the case is heard under the Federal Rules of Civil Procedure, the Federal Rules of Criminal Procedure and the Federal Rules of Evidence instead of state procedural rules (that is, the application of the Erie Doctrine only extends to a requirement that a federal court asserting diversity jurisdiction apply substantive state law, but not procedural state law, which may be different). Together, the laws of the federal and state governments form U.S. law . </P> <P> Suffrage, commonly known as the ability to vote, has changed significantly over time . In the early years of the United States, voting was considered a matter for state governments, and was commonly restricted to white men who owned land . Direct elections were mostly held only for the U.S. House of Representatives and state legislatures, although what specific bodies were elected by the electorate varied from state to state . Under this original system, both senators representing each state in the U.S. Senate were chosen by a majority vote of the state legislature . Since the ratification of the Seventeenth Amendment in 1913, members of both houses of Congress have been directly elected . Today, U.S. citizens have almost universal suffrage under equal protection of the laws from the age of 18, regardless of race, gender, or wealth . The only significant exception to this is the disenfranchisement of convicted felons, and in some states former felons as well . </P> <P> Under the U.S. Constitution, the national representation of U.S. territories and the federal district of Washington, D.C. in Congress is limited: while residents of the District of Columbia are subject to federal laws and federal taxes, their only congressional representative is a non-voting delegate; however, they have been allowed to participate in presidential elections since March 29, 1961 . Residents of U.S. territories have varying rights; for example, only some residents of Puerto Rico pay federal income taxes (though all residents must pay all other federal taxes, including import / export taxes, federal commodity taxes and federal payroll taxes, including Social Security and Medicare). All federal laws that are "not locally inapplicable" are automatically the law of the land in Puerto Rico but their current representation in the U.S. Congress is in the form of a Resident Commissioner, a nonvoting delegate . </P> <P> The state governments tend to have the greatest influence over most Americans' daily lives . The Tenth Amendment prohibits the federal government from exercising any power not delegated to it by the States in the Constitution; as a result, states handle the majority of issues most relevant to individuals within their jurisdiction . Because state governments are not authorized to print currency, they generally have to raise revenue through either taxes or bonds . As a result, state governments tend to impose severe budget cuts or raise taxes any time the economy is faltering . </P>

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