Not a ton to elaborate on, it just isn't precedent.
All jury nullification is is a jury finding someone not guilty despite the fact that they think they did actually commit all the elements of the offense. It doesn't prevent the law from being applied in future trials, even in identical situations (nor do other jury verdicts). It's not even typically known whether or not the jury found not guilty because of nullification or because they didn't find the prosecutions case convincing.
