Inquisitorial system

An inquisitorial system is a legal system where the court or a part of the court is actively involved in investigating the facts of the case, as opposed to an adversarial system where the role of the court is primarily that of an impartial referee between the prosecution and the defense. Inquisitorial systems are used primarily in countries with civil legal systems as opposed to common law systems. Countries using common law, including the United States, may use an inquisitorial system for summary hearings in the case of misdemeanors such as minor traffic violations. The distinction between an adversarial and inquisitorial system is theoretically unrelated to the distinction between a civil legal and common law system. Some legal scholars consider inquisitorial misleading, and prefer the word nonadversarial. The function is often vested in the office of the public procurator, as in Russia, China, Japan, Germany, and Scotland.

In an adversarial system, judges focus on the issues of law and procedure and act as a referee in the contest between the defense and the prosecutor. Juries decide matters of fact, and sometimes matters of the law. Neither judge nor jury can initiate an inquiry, and judges rarely ask witnesses questions directly during trial. In some American jurisdictions, it is common practice for jurors to submit questions to the court that they feel were not resolved in direct or cross-examination. After testimony and other evidence are presented and summarized in arguments, the jury will declare a verdict (literally: "the spoken truth") and in some jurisdictions the reasoning behind the verdict. However, the discussions among jurors cannot be made public except in extraordinary circumstances. Appeals on the basis of factual issues, such as sufficiency of the sum total of evidence that was properly admitted, are subject to a standard of review that is in most jurisdictions heavily deferential to the judgment of the fact-finder at trial, be that a judge or a jury. The failure of a prosecutor to disclose evidence to the defense, for example, or a violation of the defendant's constitutional rights (legal representation, right to remain silent, an open and public trial) can trigger a dismissal or re-trial. In some adversarial jurisdictions (e.g., the United States), a prosecutor cannot appeal a "not guilty" verdict (absent corruption or gross malfeasance by the court).

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