Laws are supposed be passed by a simple majority vote. Enforcing these new laws, however, is supposed to be a much more difficult proposition. The Jury is responsible for seeing to it that no law can be enforced, if it infringes on our natural rights.
There's a very good reason for having 12 jurors. One juror is all it takes to nullify any law. Since all 12 jurors must vote in agreement with the law, we essentially have a 100% resolution project already existing on our books.
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"It is left... to the juries, if they think the permanent judges are under any bias whatever in any cause, to take on themselves to judge the law as well as the fact. They never exercise this power but when they suspect partiality in the judges; and by the exercise of this power they have been the firmest bulwarks of English liberty." --Thomas Jefferson to Abbe Arnoux, 1789. ME 7:423, Papers 15:283
"If the question before [the magistrates] be a question of law only, they decide on it themselves: but if it be of fact, or of fact and law combined, it must be referred to a jury. In the latter case of a combination of law and fact, it is usual for the jurors to decide the fact and to refer the law arising on it to the decision of the judges. But this division of the subject lies with their discretion only. And if the question relate to any point of public liberty, or if it be one of those in which the judges may be suspected of bias, the jury undertake to decide both law and fact. If they be mistaken, a decision against right which is casual only is less dangerous to the state and less afflicting to the loser than one which makes part of a regular and uniform system." --Thomas Jefferson: Notes on Virginia Q.XIV, 1782. ME 2:179
"The juries [are] our judges of all fact, and of law when they choose it." --Thomas Jefferson to Samuel Kercheval, 1816. ME 15:35
"We all know that permanent judges acquire an esprit de corps; that, being known, they are liable to be tempted by bribery; that they are misled by favor, by relationship, by a spirit of party, by a devotion to the executive or legislative; that it is better to leave a cause to the decision of cross and pile than to that of a judge biased to one side; and that the opinion of twelve honest jurymen gives still a better hope of right than cross and pile does." --Thomas Jefferson to Abbe Arnoux, 1789. ME 7:423, Papers 15:283