Jury, in common law, body of laypeople assembled to study evidence and make judgments in legal proceedings. In England, the jury was probably an extension of the Norman practice of calling character witnesses, people who had personal knowledge of a dispute. Over time, the make-up of the jury changed: disinterested parties were presented with formally produced evidence. This system was adopted from English law into the United States in the 18th century. The sixth and seventh amendments to the U.S. Constitution provide for jury trial in most criminal and civil cases. A grand jury (12–23 people) hears evidence and decides whether a trial is justified; a petit (small) jury of 6 or 12 people sits at the trial proper. Until 1970, verdicts had to be unanimous, but certain exceptions are now permissible. A hung jury (one that is unable to reach a verdict) necessitates a new trial with a new jury.