1. general explanation
Guys, the key to understanding this article (in which the point was not mentioned very explicitly) is that in at least the American court system, jurors find facts, and the judge finds law. These two things are distinct. ("what happened"; "what is the legal implication.") Technically, Jurors don't need to know any law at all. Practically though, they need to know enough to decide how finely to slice the fact.
in other words, on some abstract level the jury doesn't even have to know what the law says; they only have to decide what happened. Practically though, for example in first, second, etc, degree murders, it's not enough information for the judge to hear "Yes, he killed the guy." The judge really needs to know the facts more precisely, i.e. compared with some definitions/demarcations the judge provides. (And which the jury frequently asks for clarifications on, so that they can report on their findings of what happened in terms of those definitions.)
This is also why sentencing is always done by the judge, not the jury: only the judge knows the law, the jury can only find facts.
it's also why "jury nulification" is kind of a hack of the system. If the jury doesn't like a marijuana ban, they can "nullify" by finding that despite the video tape of the guy smoking a joint, which is now in front of them, they find that the guy did not smoke pot. This supposedly circumvents a judge's ability to apply the law for it, since the jury says they find it didn't happen (wasn't proven.)
This is likewise kind of a "hack" in that the judge, knowing that the law is his to interpret, just told the jury the implication up-front, similarly as if they had heard that sentence after their verdict. But then he did not pass that sentence (actually make that interpretation of law).
This would be like telling the jury that if a bystander knowingly let you die (you're watching the case from the heavens - the bystander is on trial), that's manslaughter by negligence. The jury finds that the bystander was, in fact, guilty of negligent manslaughter for the reason of failing to rescue when he could and was in no danger.
Then the judge finds (which was his plan all along) that in the US there is 0 duty to rescue in this situation and the bystander is completely innocent of any negligence for not rescuing you, which he had no duty to do.
This way, according to the article, if another court disagrees with this interpretation of law, they already have the jury's findings and can just overturn the judge's interpretation.
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EDIT.
2. an interesting theory of the past few weeks' news.
I just thought of an interesting additional theory. The article says that both the Prosecution and Defense were OK with this approach. (Presumably, the prosecution, because that's what they were suing for in the first place, and the defense, because it thought the law was on its side and could appeal on those grounds if the judge actually sentenced per his request for the jury to assume). Now you remember how the jury was hung on whether it was 'fair use'? Given that neither defense nor prosecution tried to argue with the law, perhaps one or more members of the jury simply saw that this was a case of using copyright like a patent is normally to be used for - even though the judge told them to assume that it was copyright infringement if it happened in this case - and thought that it was therefore unfair and inappropriate. Even the defense didn't argue the point that it was not actually copyright infringement (we just found out why) so maybe one or more members of the jury said to themselves: Well, we are told to assume that this - mimicking work-alike functionality - is copyright infringement. But unless there's a patent, we just don't think it is! So, it HAS to be fair use.
If there were even a couple of jurors who were perplexed why the defense wasn't arguing that the work-alike functionality constituted copyright infringement, they might have been the ones who helped hang on whether this is fair use. The jury was perplexed, because they were given a definition of the law that is wrong!
It does show the danger of a judge taking this approach. (e.g. in my example in point 1, if a single juror knows that there's no duty to rescue in general, then maybe the jury will get hung on whether the 'negligent manslaughter' was in fact 'in self defense.' This is an ABSURD thing to actually get hung up on - but they are doing so (maybe, according to this theory of mine) because of the wrong reading of the law that they were given.)
So, with this interpretation, the past few weeks of this case are: "Jury finds bystander guilty of homocide for not helping! Jury still hung on whether homicide was in self-defense. (later..i.e. today.) Judge reveals that he told the jury to assume, in making their finding, that failing to rescue when this would pose no risk to the rescuer constituted negligent homocide, and that both the defense (sure of the actual law or grounds for appeal if this is the actual finding of law by the judge in the end) and prosecution went along with this.
If this theory is correct, it gives a VERY different reading to the way the jury acted and found. In fact, it paints them as downright reasonable, within the constraints of their (manipulative, hypothetical) instructions.