Every judge in every jurisdiction writes there own jury instructions in these matters. That does not make them law, that makes them a judges personal opinion.
When you sit on a jury you will find that the vast majority of these jurors have absolutely no concept of the law. Thats why when you get on the jury you must be as articulate as possible to explain your position of why you find the defendant not guilty. It is enough that one person stands up and votes not to convict, but it is even better if you can convince the other 11 jurors why the vote to acquit is the correct one. One vote to acquit will save that persons life temporarily, but the prosecutor will recharge and in all likelihood even charge the defendant with a more serious crime than first charged. But if you can persuade the other jurors to acquit he can never be charged with that crime again. Though he will still remain a target. I highly recommend that any defendant that has been acquitted in one of the cases that they move to another jurisdiction. He will be targeted for re arrest, he will targeted for retribution. It does happen. I've sat on juries where this exact thing has taken place. The cops, the prosecutors, the judges, are not your friends, they are not there to help. Educate yourself on your legal responsibilities so that you too can have knowledge on how to play the game called judicial process.