Explain the history of the 12-member jury requirement.
Juries have consisted of 12 members since as far back as the 1300s in English law. However, in 1898 the American Supreme Court formally upheld the view that 12 jury members should be a constitutional requirement. Almost a century later during the case of Williams v Florida (1970), the Court amended its view, stating that the Sixth and Fourteenth Amendments also allowed for a 6-person jury. However, because of justice dissent on this issue concerning trials at the state level throughout the following decade, the Court changed its view again finally in 1979. It held that if 6-person juries are allowed, verdicts may only be unanimous. Otherwise, non-unanimous verdicts would be in violation of a defendant's constitutional right to trial by jury, as provided under the Sixth Amendment.