Leaving OJ to his own devices for a moment...
There's two issues being discussed here: the arrest of the person passing out literature discussion "juror nullification" and the concept of juror nullification.
Regarding the former issue: the article listed appears to be a special pleading, and there is nothing wrong with that. It does, however, leave a number of questions unanswered. In particular, was the person charged approaching people entering the courthouse or was he targeting people who had already been empaneled as jurors. There's a significant difference.
Those who were reporting for jury service were not yet jurors. They hadn't gone through voir dire nor had they been sworn. If this is the case, and he was passing out his literature to any and all who would take it on the courthouse steps, then I see no reason to charge him. If, on the other hand, he was targeting already enpaneled jurors, particularly if they were on a particular case, then his actions could be construed as an attempt to affect the jury's consideration of the facts of the case.
Regarding juror nullification: yes, it has long existed, but in many cases it is not the "strike for freedom" that some may ascribe as the motivation. Jurors have wrongly convicted, even if the evidence was very weak, because they thought the defendant deserved it. This is almost lynching with a veneer of judicial respectability. As said earlier, juror nullification--that is ignoring the law as presented--is the substitution of the decisions of six or twelve citizens for the majority will, acting through their elected representatives.
In the American system of justice the jury acts as the "trier of fact," while the judge is the "trier of law." It is the sovereign right of the jury to determine the credibility of witnesses, weigh the physical evidence, and draw appropriate conclusions--in other words determine the facts--from what has been properly presented to them, then make a decision if those facts and conclusions meet the requirements of the law that has been presented to them as instructions from the court.
It is up to the judge to determine how to apply the law which has passed by a duly elected legislature. The prosecution and defense counsel certainly have a chance to argue their own view of the law, argument that the jury never sees as it isn't their responsibility. The judge may also determine that the particular law is conflict with higher laws. And of course there's the ability to appeal the judge's determination. This is what jury nullification attempts to sidestep, and that's why it is looked upon with disfavor.
