A jury is a selected number of individuals (jurors) who have sworn (ie taken a solemn oath) to reach a fair decision on matters of fact in a court.

In England and Wales, juries are required to reach a verdict on the evidence in criminal trials for indictable offences, tried in the Crown Court, and to determine the cause of death in some inquests, held in a coroner’s court. In criminal trials, the number of jurors is 12 (between the ages of 18 and 75, randomly selected from the electoral roll), though a case can continue with as few as nine if for any reason individual jurors are prevented from continuing.

Juries are occasionally used for certain types of civil case in England and Wales, such as defamation, but this happens increasingly rarely.

In other jurisdictions, the role and number of jurors may vary.