In civil cases the plaintiff claims to have suffered a loss and usually seeks damages from the defendant. The defendant argues either that the loss did not occur or that the defendant is not responsible for it. Lawsuits may involve property disputes, breach of contract, or family matters, such as divorce. If the suit is not settled, the case goes to trial.
Criminal cases can be divided into crimes against people, crimes against property, and victimless crimes. Officers make arrests if they have witnessed a suspected crime, if a citizen has made a complaint or reported a crime, or if a judge has issued an arrest warrant. A preliminary hearing is followed by an indictment by a grand jury and arraignment. In many cases the prosecution and the defendant may reach a plea bargain. This is an agreement in which the accused person agrees to plead guilty, but to a lesser charge. If the case goes to trial, guilt or innocence will be determined by a jury or a judge.
In most states anyone under 18 is considered a juvenile, or someone not yet legally an adult. All states and the federal government allow juveniles who are charged with very serious crimes to be tried as adults. The juvenile justice system is able to treat young people in ways that are different from the adult system. The primary purpose of juvenile courts is to try to rehabilitate the person.