The Sixth and Seventh Amendments of the United States Constitution guarantee the right to trials by jury in criminal and civil cases respectively. The Sixth Amendment has been incorporated into the Fourteenth Amendment, and therefore applies to all of the states. Although the Seventh Amendment has not been formally incorporated into the Fourteenth Amendment, nearly all of the states assure jury trials in civil as well as criminal actions. The history of the American jury system traces its origins to tenth century England. 

King Æthelred II (r. 978-1016) of England introduced what is thought to be the first English legal code, which required thegns (local nobles) to investigate crimes that occurred under their dominion. Unlike modern common-law jury trials in which facts are presented to a jury by the parties to the proceedings during a trial, the thegns were required to discover the facts of each case before them on their own. 

King Henry II (r. 1154-1189) established a jury system in which juries composed of twelve free men were tasked with solving land disputes. Like the thegns under King Æthelred’s legal code, rather than learning the facts of a case through the presentation of evidence in court, these free men investigated each case on their own to determine its facts. King Henry II also introduced grand juries of free men. Members of grand juries were instructed to report any crime that occurred within their hundred (a division of land) to a justice in the eyre, who rode around the circuits of England on horseback. Accused criminals were subjected to a trial by ordeal, often by combat, fire, or water. During a trial by combat, the two parties of a dispute would fight and the losing party was deemed guilty. A trial by fire required the accused party to either walk a certain distance carrying a red-hot iron or to walk over red-hot plow blades. The distance the accused was required to walk depended on the severity of the crime of which he or she had been accused. The accused could prove his or her innocence either by emerging from the task un-injured, or if the accused’s wounds on the premise that if the accused wounds had healed by three days after the ordeal took place then God must have intervened to heal the accused’s wounds and, therefore, the accused party must be innocent. If the wound did not heal or began to fester, the accused was found guilty of the crime.

Twelfth century image depicting a trial by fire.

Trial by water required an individual accused of a crime to fetch a rock from a kettle of boiling water. The depth at which the rock was placed depended on the severity of the crime the individual was accused of committing. As in cases of trial by fire, a priest examined the accused’s wounds three days after the ordeal to determine whether God had healed the accused’s wounds, thus proving his or her innocence.

A man accused of a crime grabbing a rock out of a kettle of boiling water.

By 1215, the Church banned the participation of the clergy in trials by ordeal and trials by ordeals ceased to be conducted. Juries began deciding an individual’s guilt or innocence based on secular evidence. The Magna Carta, signed on Christmas day in 1215, made trial by jury a right for free men. By the fourteenth century, England forbade members of its grand juries from sitting on the trial jury for the same crime. The trial jury was tasked with finding out the facts of the case. Individuals who were familiar with the crime or the parties were often chosen to sit on the trial jury to save the government the time and cost associated with fact-finding. Over time, juries began relying on a trial to present them with facts, which they would use to decide the guilt or innocence of the accused. By the seventeenth century, juries were forbidden from investigating the facts of the case on their own, and juries thus relied entirely on the information presented to them at a trial itself to provide them with the facts of each case. 

The Star Chamber, a court at the palace of Westminster, operated from the fifteenth to the late-seventeenth centuries. In his Survey of London (1598), John Stow, an English historian, explained that the Star Chamber was so named because “all the roofe thereof was decked with images of stares gilted.”  The Star Chamber was initially intended to provide a fair trial for those so powerful that the lower courts might be unwilling to convict them. The Star Chamber was composed of Privy Councilors and common-law judges. 

1873 Engraving of the Star Chamber in the Palace of Westminster showing the “gilted” ceiling.

Although the Star Chamber was initially a just and efficient court, it eventually became used as a tool of political oppression. The Star Chamber often heard cases on appeal from lower courts. It also served as a court of equity for “morally reprehensible” acts (such as sedition, perjury, and conspiracy) which did not violate England’s legal codes. The Star Chamber grew tremendously in power because it began convicting individuals for legal actions that it felt should be unlawful. It began to apply the laws of England arbitrarily and monarchs began to use the Star Chamber as a political weapon against everyone who opposed their policies. Defendants were forced to swear an ex officio oath, a religious oath to promise to truthfully answer every question asked during the trial. Because testimony was compulsory, the defendants could be faced with a “cruel trilema.” Defendants were forced to incriminate themselves, to be held in contempt of the court if they refused to answer a question, or to commit perjury, which is considered a mortal sin. The Habeas Corpus Act of 1640 abolished the Star Chamber and guaranteed the right of the accused to be tried and judged by his or her own impartial peers. 

1555 engraving of Henry VIII with his council in the Star Chamber.

The English monarchy’s use of the Star Chamber as a political weapon influenced the Framers of the United States Constitution to include a protection against self-incrimination. The Fifth Amendment, which was ratified in 1789, protects individuals from being forced to bear witnesses against themselves, and virtually guarantees that prosecutors may not insinuate that a defendant is guilty for refusal to testify in his or her own defense and that judges must instruct jury members that they may not draw such an inference of guilt.

Many of England’s colonies, including the United States, adopted a similar adversarial legal system in which plaintiffs and defendants are represented by advocates who present the facts of the case to a jury or a judge, who decide the outcome of the case. Criminal defendants may waive the right to a jury trial, as may the parties to civil actions. Additionally, trials on certain types of actions, including divorces, probate, and juvenile criminal matters are always tried before a judge. Although parties filing for bankruptcy technically have the right to have their cases heard by a jury, they rarely invoke this option. Cases heard by a judge as trier-of-fact are known as bench trials.

Image depicting jury deliberation in the 1957 film 12 Angry Men.