The Rights of the Accused during Trial
The Adversarial System
American justice is based on the adversarial, or accusatory, system, as opposed to the inquisitional system. Under the latter, a magistrate--or a king or religious official--takes an active role in determining facts and making judgments, while defense lawyers (assuming any are allowed) remain in the background, only speaking when asked to speak. This description calls forth a number of images, none of them pleasant: the Spanish Inquisition or various other religious witch hunts, France under Louis XIV, the "kangaroo courts" of Nazi Germany and Stalinist Russia, or the Islamic fundamentalist system in Iran under the Ayatollah Khomeini. It is almost by definition a method in which the accused is guilty until proven innocent.
Under the adversarial system, the roles are reversed: lawyers, both for the defense and the state, take an active part in the proceedings, while the magistrate assumes the passive position of a referee. In both situations, the magistrate maintains control over the courtroom, but in the adversarial scenario, he or she acts merely as the servant of the law, not as its source. Again, almost by definition, it is a system in which the accused is innocent until proven guilty. Thus the burden of proof is on the government, and guilt must be proven beyond all reasonable doubt.
Additional topics
Law Library - American Law and Legal InformationGreat American Court CasesThe Rights of the Accused during Trial - The Adversarial System, The Burden Of Proof, The Right To Counsel, Witnesses And The Right Of Confrontation