ABA Family Legal Guide

How the Legal System Works

Introduction to the Legal System

What is the idea behind our legal system?

We have what is known as an adversarial legal system, because it is believed that the truth in a matter can best be determined by giving two sides an equal chance to make their case before an impartial judge or jury.

Our adversarial system has several essential features. Each side has a right to be represented by a lawyer, whose job it is to argue why the court should apply the law to the facts in a particular way. Each lawyer is bound by the same statutes, case law, and rules of procedure as his or her adversary. The judge is neutral and impartial, and ensures that the presentation of evidence and questioning of witnesses are carried out according to the rules of procedure. The trial procedure is based on rules, statutes, and historical precedent, modified, as necessary, by the changing needs of the justice system, and based on the experience of lawyers, judges, and litigants.

This is the basic pattern for both criminal cases (in which the government accuses someone of violating a criminal law and the defendant may face a fine or jail time) and civil cases (in which a private person or business sues another person or business, typically to seek damages for noncriminal conduct, such as a broken contract or a personal injury). However, as noted in the next several answers, the two types of cases differ in many particulars.