Laws serve five main functions in a democratic society. They offer security, supply predictability, provide for conflict resolution, reinforce society's values, and provide for the distribution of social costs and benefits. American law is based on legislation, but its practice has evolved from a tradition of common law and the use of precedent by judges.
The American legal system is considered to be both adversarial and litigious in nature. The adversarial nature of our system implies that two opposing sides advocate their position with lawyers in the most prominent roles, while the judge has a relatively minor role in comparison.
Laws serve many purposes and are classified in different ways. Substantive laws cover what we can or cannot do, whereas procedural laws establish the procedures used to enforce law generally. Criminal laws concern specific behaviors considered undesirable by the government, whereas civil laws cover interactions between individuals. Constitutional law refers to laws included in the Constitution as well as the precedents established over time by judicial decisions relating to these laws. Statutory laws, administrative laws, and executive orders are established by Congress and state legislatures, the bureaucracy, and the president, respectively.The founders were deliberately vague in setting up a court system so as to avoid controversy during the ratification process. The details of design were left to Congress, which established a layering of district, state, and federal courts with differing rules of procedure.
The Constitution never stated that courts could decide the constitutionality of legislation. The courts gained the extra-constitutional power of judicial review when Chief Justice John Marshall created it in Marbury v. Madison.
The political views of the judge and the jurisdiction of the case can have great impact on the verdict. The rules of the courtroom may vary from one district to another, and the American dual court system often leads to more than one court’s having authority to deliberate.
The U.S. Supreme Court reigns at the top of the American court system. It is a powerful institution, revered by the American public but as political an institution as the other two branches of government. Politics is involved in how the Court is chosen and how it decides a case, and in the effects of its decisions.
Although the U.S. criminal justice system has made progress toward a more equal dispensation of justice, minorities and poor Americans have not always experienced equal treatment by the courts or had equal access to them.