When to use force is a tricky legal matter. To get it straight, I just bought How to Own a Gun & Stay Out of Jail (California Edition 2002). It is especially tricky in California, where they keep passing anti-gun laws. The law says you can use reasonable force to defend yourself. One common misconception is that reasonable force with a gun means shooting someone in the leg. In reality, it is rarely advisable to shoot someone in the leg. It nearly always preferable to either not shoot, or to shoot to kill. You only want to shoot if your life is in imminent danger, and in that case, merely shooting someone in the leg probably won't be good enough to stop the attack.
George writes, "Isn't jury nullification a violation of the oath that jurors take?"
The judge may ask a juror: "And will you promise to obey any instructions in the law I may give you, even should you disagree with one or more of them?"
I would answer yes to this question. The judge is the boss in the courtroom, and it is his job to explain and apply the law. The presumption is that he is doing his job properly, and giving lawful orders. But it is the jury's constitutional duty to render a verdict based on the totality of the info available. That
may mean jury nullification, as the constitutional duty is greater than any obligation to accept the opinion of some particular judge. After all, judges get overruled by higher courts all the time.