The duty of a juror is to protect his community; both from dangerous criminals and from dangerous laws. The jury is the highest authority in the courtroom; towering above the judge. Judges don't like for the juries to recognize the pecking order, so they try to frighten jurors into complying with their demands. Judges lie and tell jurors to only consider the facts of the case, which is only half- the weaker half, of the jury's historical duty. You hold the power of jury nullification of counterfeit "laws". It is an awesome power and responsibility and one that causes judges (and corrupt government at every level) to tremble in fear. The time to understand the power and authority of the jury is before you get called for jury duty. If you find yourself sitting on a jury, remember: if the law that was violated is counterfeit (attempts to regulate something other than initiated, actual force or fraud) you must find the defendant innocent, even if you don't like the person. Even if you are sure the person is a scum who has committed real crimes in the past and probably will again. That will be dealt with at a later date. Your bigger responsibility at that point is to protect your neighbors from a "law" that has much greater potential for harm that any two-bit thug could ever hope to have. Then you can go on to warn your neighbors of your suspicions about the defendant.
Become acquainted with the Fully Informed Jury Association and go to www.fija.org to read more about the job of a juror.