What is one of the major roles the supreme court plays in federal judiciary

The Supreme Court of the United States is the highest federal court in the legal system of the United States, located in Washington DC.

The Supreme Court is the only US court that is specifically included in the Constitution of the United States. In addition, Congress established 95 Federal District Courts and thirteen Federal Courts of Appeals. These are respectively the federal courts of first instance and the federal courts of appeal.  

The Federal Courts deal with matters that concern the US Constitution, federal law or federal treaties. In addition, they are responsible for maritime law and for matters involving foreign citizens or governments or the US federal government itself.

With some exceptions, only appeals are handled by the Supreme Court. Most of these cases involve disputes about the interpretation and constitutionality of the acts and laws introduced by Congress or by individual states.

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