陪審 | 定義、選出と役割 | ブリタニカ

Jury | Definition, Selection & Role | Britannica Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos jury Introduction History and use Jury procedures Selection Size and unanimity Sentencing Control The controversy over the jury Jury performance References & Edit History Related Topics At a Glance jury summary print Print Please select which sections you would like to print: Table Of Contents CITE verified Cite While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions. Select Citation Style MLA APA Chicago Manual of Style Copy Citation Share Share Share to social media Facebook X URL https://www.britannica.com/topic/jury Feedback External Websites Feedback Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login). Feedback Type Select a type (Required) Factual Correction Spelling/Grammar Correction Link Correction Additional Information Other Your Feedback Submit Feedback Thank you for your feedback Our editors will review what you’ve submitted and determine whether to revise the article. External Websites Law Teacher - The Jury System National Geographic - Jury Britannica Websites Articles from Britannica Encyclopedias for elementary and high school students. jury system - Student Encyclopedia (Ages 11 and up) jury Ask Anything Quick Summary Homework Help Written by Harry Kalven Harry A. Bigelow Professor of Law, University of Chicago, 1953–74. Coauthor of The American Jury. Harry Kalven All Fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors Last updated Mar. 29, 2026 • History Britannica AI Ask Anything Quick Summary Table of Contents Table of Contents Quick Summary Ask Anything Top Questions What is a jury? What does a jury do in a court case? How are jurors chosen for a jury? What types of cases use a jury? How does a jury reach a decision or verdict? Why is serving on a jury considered an important civic duty? Show more Show less jury , historic legal institution in which a group of laypersons participate in deciding cases brought to trial . Its exact characteristics and powers depend on the laws and practices of the countries, provinces, or states in which it is found, and there is considerable variation. Basically, however, it recruits laypersons at random from the widest population for the trial of a particular case and allows them to deliberate in secrecy, to reach a decision by a vote, and to present its verdict without giving reasons. (In 2017 the U.S. Supreme Court held that the federal rule that prevents former jurors from testifying about the deliberations of the jury on which they served could be suspended in cases in which there is clear evidence that a juror made statements during deliberations indicating that his or her vote to convict the defendant was significantly motivated by racial animus.) Throughout its history, it has perhaps been both overpraised as a charter of liberty and overcriticized as a reliance on incompetent amateurs in the administration of justice . History and use The origin of the jury is disputed. It may have been indigenous to England or have been taken there by the Norman invaders in 1066. Originally, the jurors were neighbourhood witnesses who passed judgment on the basis of what they themselves knew. The breakdown of medieval society and the growth of the towns changed the role of the jury, which came to be called upon to determine the facts of the case on the basis of the evidence presented in court . The availability of the jury in the king’s courts may have been a key factor in centralizing the country’s courts under the king and in creating the common law . By the 15th century, nonrational modes of trial such as ordeal , in which the defendant was subjected to various tortures, were replaced by the jury trial, which became the established form of trial for both criminal and civil cases at common law. Two forces extended the jury outside England. The expansion of the British Empire brought the jury to Asia, Africa, and the American continent, and the French Revolution and its aftermath brought the jury, as a symbol of popular government, to the European continent. Juries were first established in France itself; through Napoleon , the jury was introduced first in the Rhineland, then in Belgium, and finally in most of the remaining German states, Austria-Hungary, Russia, Italy , Switzerland, Holland, and Luxembourg. However, the last two countries abolished it immediately after Napoleon’s defeat. In each of these countries, use of the jury was limited to trials of major crimes and of political crimes against the state. Beginning in the mid-19th century, the jury was weakened in a variety of ways. For example, in 1850 Prussia removed treason from its jurisdiction; in 1851 the duchy of Nassau removed all political crimes; in 1923 Czechoslovakia removed treason and, one year later, libel; in 1919 Hungary suspended trial by jury entirely and never restored it. Germany abandoned the jury in 1924. Both the Soviet bloc and the fascist states abolished it outright; France never restored the jury abolished during the German occupation in the 1940s, and Japan did away with its short-lived jury courts in 1943. After World War II , Austria reintroduced the jury in a weakened form. Thus, the history of the jury shows that the effort to introduce it outside the Anglo- American legal orbit largely failed. In England its use was limited by statute to a small category of cases. Consequently, the United States emerged as the home of the jury system for both criminal and civil cases; more than 90 percent of all jury trials in the world occur in the United States. Use of the jury in the United States depends on two factors: the degree to which it is available as a matter of right and the degree to which the parties choose to use it. The availability of the jury trial varied from state to state, but, in 1968 in Duncan v. Louisiana , the United States Supreme Court ruled that a jury trial is a constitutional right in all criminal cases in which the penalty may exceed six months’ imprisonment. In civil cases its constitutional status is more various, but jury trial generally is available in all U.S. states and in the federal courts. The practice of allowing the parties to waive a jury trial also varies widely from region to region. Jury procedures Selection Historically, there were requirements of property and competence for jury service. The genuine random selection of jurors from the general population (to achieve a cross section of the community) gained ground and became the principle of selection in the federal courts and most state courts. Most jurisdictions exempt some groups from jury service (e.g., police officers, lawyers, doctors, etc.). All jurisdictions excuse jurors if the service imposes undue hardship. Related Topics: grand jury petit jury death-qualified jury blue-ribbon jury jury selection (Show more) See all related content Explore Britannica Premium! Go beyond the basics with trusted, in-depth knowledge for professionals, students, and lifelong learners. SUBSCRIBE The commitment of important decisions to a random group of laypersons has been moderated, particularly in the United States, by an elaborate screening process known as voir dire , which is conducted by trial counsel at the inception of a trial. The law permits counsel to challenge prospective jurors either for cause (if there is specific likelihood of bias) or, for a limited number, “peremptorily” (i.e., without having to give a reason). American trial tradition attaches a great deal of significance to the strategies of juror selection, and in high-profile cases the lawyers’ voir dire examination has sometimes extended for several weeks.