Of all constitutional rights, none of them have a longer or more auspicious pedigree than that of trial by jury, which is guaranteed no less than three times in the Constitution and Bill of Rights. First, the Founding Fathers guaranteed citizens accused of crime a trial by jury in Article III Section 2. That wasn't good enough, though. Fearing people might be tried away from their homes, friends, and families, they drafted the Sixth Amendment, guaranteeing that the trial would take place in the same district in which the crime was committed. Then, for good measure, they guaranteed civil litigants trial by jury in any case in which more than $20 was at stake. No other guarantee in the Constitution made the Founders be repetitive the way jury trial did --and for good reason.
Prior to the Revolution, the British transferred cases involving the Crown into the Maritime Courts, where there were no juries. They did this for an obvious reason--Colonial jurors were unwilling to convict their neighbors in cases where the laws were unjust. In 1735, John Peter Zenger was acquitted of printing criticisms of the royally appointed Governor of New York because the jury believed the criticisms were true. Although they had been instructed that the truth of a libel was no defense, the jurors believed it would be absolutely unjust to convict, and "just said no." Zenger went home a free man, and his lawyer, Andrew Hamilton, was given an award for his representation. Freedom of speech, encompassed in the First Amendment to the Constitution, became part of the bedrock of American liberties.
Freedom of religion was recognized by juries 65 years earlier, when William Penn and William Mead were acquitted of tumultuous assembly for preaching the Quaker religion in Gracechurch Street, London. They were preaching in the street because they had been locked out of their meeting-house by the constables, the Quaker religion being proscribed by English law. A jury, after three days without food, water, or toilet facilities, acquitted Penn and Mead, thus establishing freedom of religion decades before it was officially recognized in the law.
As a reward for their service, Penn's jurors were themselves incarcerated for their verdict. On their appeal, it was ruled that, because "a man cannot see by another's eyes, nor hear by another's ears," no jurors could be prosecuted or punished for their verdict. This remains the law today. A juror may freely vote his or her conscience, without fear of reprisal by the judge, prosecutor, or police. Moreover, if the jury acquits, the verdict is absolutely final. The Fifth Amendment to the Constitution guarantees freedom from double jeopardy. Once a defendant is acquitted, the state cannot try again. The case is over.
Because jurors cannot be punished for their verdict, they have an unambiguous power to acquit guilty defendants. Occasionally, they do just that--a process called jury nullification. The power to nullify, protected as it is in the Constitution, exists to prevent oppression by the government, allowing private citizen jurors to veto governmental overreaching. However, the government does not like to be vetoed. Jury nullification has become a relentless source of tension between civil libertarians and government authorities.
History, as well as modern social science, shows that jurors tend to nullify either unpopular laws or overzealous applications of popular ones. The Alien and Sedition Acts and the Fugitive Slave Acts were frequently the target of nullifying jurors, as was Prohibition. In more recent years, Vietnam War protestors, motorcycle helmet law opponents, midwives, abortion protestors, right-to-die advocates, and users of marijuana for medicinal purposes have all benefited from juries that decided the law before them was just plain wrong. Juries also have nullified when they believed defendants faced sentences that were draconian under United States Sentencing Guidelines or "three strikes" laws. …