jury, body convened to make decisions of fact in legal proceedings.

Development of the Modern Jury

Historians do not agree on the origin of the English jury. Although some authorities trace it to Anglo-Saxon or even more remote Germanic times, most believe that it was brought to England by the Normans. The first jurors were not triers of fact in legal disputes but were persons acquainted with the situation in question who spoke out of personal knowledge. Thus, in compiling the Domesday Book inquests of neighbors were convened to furnish information on property holdings.

In the enforcement of criminal justice the earliest function of the jury (mid-12th cent.) appears to have been the presentation of accusations, and it was only later that jurors were convened to answer on oath the question of guilt. These early jury trials, while supplanting the ordeal and other irrational procedures, were not themselves satisfactory, because they depended entirely on the unsupported oath of the jurors. A verdict could not be overturned except by attaint, that is, by summoning a second jury to give its sworn verdict on the question as to whether the first jury had committed perjury.

By the 16th cent. the jury was used in civil as well as criminal cases, and the practice of calling witnesses was well developed. However, not until the mid-18th cent. were methods other than the attaint available to set aside an improper verdict.

To the English and other peoples who have adopted the English common-law system, trial by jury became a cherished protection against the possibility of judicial and administrative tyranny. Among the abuses recited in the American Declaration of Independence is "depriving us in many cases, of the benefits of Trial by Jury." The Sixth and Seventh Amendments to the U.S. Constitution, reflecting this concern, require a jury in federal trials, in criminal prosecutions, and in civil suits at common law where the damages sought exceed $20; the traditional exemption of cases in equity was left unchanged.

The merger of law and equity has led to the development of various tests to determine if a case can be tried before a jury. In 1967 the U.S. Supreme Court held that the Fourteenth Amendment guaranteed the right to a jury in state criminal trials. Most U.S. states preserve jury trials for a variety of civil cases. Great Britain has limited the use of civil juries to cases in which community attitudes are especially important (e.g., defamation and fraud).

The Modern Jury

In most criminal cases the charge is first considered by a grand jury with 12 to 23 members. It hears witnesses against the accused, and if 12 jurors believe that there is sufficient evidence to prosecute, an indictment or the like is presented. The jury sitting at the trial proper is called a petit (or petty) jury from its smaller size (usually 12 members).

The selection of a trial jury is essentially alike in civil and in criminal cases. The venire, a panel of prospective jurors living in the district where the trial is to be held, is summoned for examination. Counsel for the parties may first challenge the array, that is, object that the venire as a whole was improperly chosen or is for some reason unfit. The challenges to the poll (the members of the venire taken individually) that follow are designed to secure as jurors unbiased persons without special knowledge of the matters in issue. Included are challenges for principal cause, i.e., some grounds such as relationship to a party that requires dismissal of a member of the venire; challenges to the favor, i.e., suspicion of unfitness on which the judge rules; and a limited number of peremptory challenges. Once selected, the jury (usually with several alternates) takes an oath to act fairly and without preconceptions. At the close of the evidence and after the summations of counsel the judge instructs the jury concerning the verdict. Outside the English-speaking countries there is generally less recourse to the jury and less care in the selection of jurors.

The value of juries in civil trials is disputed. Opponents of juries argue that they are ineffective, irrational, and cause delay; proponents argue that juries bring community standards to bear, can modify the effects of harsh laws, and are a protection against incompetent judges. Critics also have argued that juries are responsible for huge, arbitrary punitive damage awards in malpractice, product liability and similar cases, but an extensive 2001 study of actual cases found that juries and judges tend award punitive damages as often and to the same degree.

grand jury, in law, body of persons selected to inquire into crimes committed within a certain jurisdiction. It usually comprises a greater number than the trial, or petit (also, petty) jury, having since early common law days had between 12 and 23 members. In the United States, federal grand juries have between 16 and 23 jurors. The grand jury receives complaints and accusations in criminal cases, hears evidence adduced by the state, and approves an indictment when satisfied that there is enough evidence against the accused to warrant a trial. It was not until the 17th cent. that the grand jury acquired its modern functions as a check on the discretion of prosecutors and a way of preventing unjustified and politically motivated prosecutions. Grand juries have investigative functions as well, and are sometimes impaneled to issue reports on, e.g., suspected official wrongdoing.

The rules governing grand jury proceedings are very different from those governing trials by (petit) jury. The public is not admitted to hearings, and witnesses can be compelled to testify. The procedure is inquisitorial rather than adversarial: the defense is not allowed to call witnesses, and the prosecutor is not obliged to present both sides of the case. Hearsay and other evidence that might be excluded at a jury trial may be introduced.

The use of grand juries has declined in the 20th cent., in part because they were perceived as prone to either prosecutorial domination or abuse of their investigatory role. Britain abandoned them in the 1930s, and today fewer than half of U.S. states employ them. The information, a written statement issued by a prosecutor, has largely replaced the indictment. The Fifth Amendment to the U.S. Constitution, however, guarantees a grand jury inquiry to anyone accused in federal court of a capital "or otherwise infamous" (i.e., a felony) crime.

or trial jury

Group chosen from the citizens of a district to try a question of fact at issue in a trial. Though petit juries in England and the U.S. historically have contained 12 members, there is no uniform number. Numerical requirements for a valid verdict vary (e.g., unanimity in most courts in the U.S., a majority in Scotland and Italy, two-thirds in Portugal). The petit jury is the standard jury for civil and criminal trials. It has less discretion than is often imagined. The trial judge supervises it, rules on what evidence it may view and which laws are applicable, and sometimes directs or, at the end of the trial, sets aside its verdict. Seealso grand jury.

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In law, a body of individuals selected and sworn to inquire into a question of fact and to render a verdict according to the evidence. Juries may deal with questions of law in addition to questions of fact, though federal juries in the U.S. are usually limited to dealing with questions of fact. The modern jury can vary in size depending on the proceeding but usually has either 6 or 12 members. By U.S. law, federal grand juries and petit juries must be “selected at random from a fair cross-section of the community in the district or division wherein the court convenes.” State jury selection varies somewhat. The Supreme Court of the United States has stated in a series of decisions that a jury is to be composed of “peers and equals” and that systematic exclusion from a jury of a particular class of people (e.g., on the basis of sex, skin colour, or ancestry) violates the equal-protection clause of the 14th Amendment to the Constitution of the United States and the defendant's right to a jury trial. A defendant is not, however, enh1d to a jury of any particular composition. Seealso grand jury; petit jury; voir dire.

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Jury that examines accusations against persons suspected of committing a crime and, if the evidence warrants it, issues formal charges on which the accused are later tried (see indictment). It does not decide guilt or innocence, only whether there is “probable cause” to believe that a person committed a crime. Public officials (prosecutors and police) provide information and summon witnesses for the jury. The proceedings are usually secret. Some U.S. states have abolished the grand jury and authorize indictments by prosecutors.

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