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).