JU'RY, n. [L. juro, to swear.] A number of freeholders, selected in the manner prescribed by law, empaneled and sworn to inquire into and try any matter of fact, and to declare the truth on the evidence given them in the case. Grand juries consist usually of twenty four freeholders at least, and are summoned to try matters alleged in indictments. Petty juries, consisting usually of twelve men, attend courts to try matters of fact in civil causes, and to decide both the law and the fact in criminal prosecutions. The decision of a petty jury is called a verdict.

If the jury feels the law is unjust, we recognize the undisputed power of the jury to acquit, even if its verdict is contrary to the law as given by a judge, and contrary to the evidence...If the jury feels that the law under which the defendant is accused is unjust, or that exigent circumstances justified the actions of the accused, or for any reason which appeals to their logic or passion, the jury has the power to acquit, and the courts must abide by that decision.

In this case, the first Chief Justice, John Jay, wrote: "It is presumed, that juries are the best judges of facts; it is, on the other hand, presumed that courts are the best judges of law. But still both objects are within your power of decision… you [juries] have a right to take it upon yourselves to judge both, and to determine the law as well as the fact in controversy"

They say that the jury has a well-recognized prerogative to disregard the instructions of the court even as to matters of law...

The general misconception is that any statute passed by legislators bearing the appearance of law constitutes the law of the land. The U.S. Constitution is the supreme law of the land, and any statute, to be valid, must be In agreement. It is impossible for both the Constitution and a law violating it to be valid; one must prevail. This is succinctly stated as follows:
The General rule is that an unconstitutional statute, though having the form and name of law is in reality no law, but is wholly void, and ineffective for any purpose; since unconstitutionality dates from the time of it's enactment and not merely from the date of the decision so branding it. An unconstitutional law, in legal contemplation, is as inoperative as if it had never been passed. Such a statute leaves the question that it purports to settle just as it would be had the statute not been enacted.
Since an unconstitutional law is void, the general principles follow that it imposes no duties, confers no rights, creates no office, bestows no power or authority on anyone, affords no protection, and justifies no acts performed under it.....
A void act cannot be legally consistent with a valid one. An unconstitutional law cannot operate to supersede any existing valid law. Indeed, insofar as a statute runs counter to the fundamental law of the lend, it is superseded thereby.
No one Is bound to obey an unconstitutional law and no courts are bound to enforce it.