Unlike the other two constitutionally established branches of government, the judiciary appears the most distant to the average citizen. The founders set up a dual court system, allowing for both state and federal courts. Although they are independent from federal courts, the state courts are linked by an appeals process that enables individuals to challenge state laws and statutes in the federal courts.

The jurisdiction of federal and state courts depends upon the nature of the cases. The Constitution specifically assigns federal courts jurisdiction in cases arising from the Constitution. The most important source of the Supreme Court's caseload is appellate jurisdiction . The supreme Court has original jurisdiction only in those "cases affecting ambassadors, other public ministers and consuls, and those in which a State shall be a party."

Even though the Supreme Court receives thousands of cases to review each year , it chooses only between 75 and 200 cases each session from state courts, circuit courts of appeal, and district courts.

State court jurisdiction involves cases deriving from state laws. Most criminal cases in state courts are decided by a plea bargain between the defense and prosecution.

Congress is empowered by the Constution to create new federal courts and specify the number of judges who will sit on them, but federal judges are appointed for life by the President, with the approval ("advice and consent") of the Senate. Supreme Court justices were given life tenure, subject to good behavior, by the framers to ensure that justices remained free from political pressure.

Presidents wishing to change the "policymaking" direction of the federal judiciary have used the appointment process to select judges with philosophies similar to their own. Sometimes, though, presidents have been surprised and horrified by the decisions of "their" judges once they have been sworn in.

Historically, the Court has tried to avoid issues in which it has to decide ("take sides") between Congress and the President.

Civil Law

Common law

Cases of Equity

Constitutional courts

Criminal law

Writ of certiorari

conservative activism