True, you would be thrown out
of the jury pool by any prosecutor worth his/her paycheck for saying that you disagreed with the law.
This is another argument for nullification not being a "right", in the legal context, since if you had a right to be on any particular jury, there would be no need for the selection process at all, as challenging a juror would be a violation of that juror's right to be on the jury. Clearly, this is not the case.
Nullification is an "emergent property" of the jury system. It exists, because there is no way to restrict the juror's ability to render a decision without destroying the whole system of trial by jury. It isn't, that I know of, codified in law or court procedure, it simply is, and there's nothing anyone can do about it.
So far as I know, there are no penalties for jurors who ignore the judge's instructions. And prosecutors can't appeal acquittals. So if you get on a jury, and choose not to convict, there's nothing anyone can do about it, regardless of your reasons. You can even state them out loud, to your fellow jurors. If there were some way to remove you from the jury for it, wouldn't that cause a mistrial anyway? Which is what you'd get if the other jurors didn't go along with your stand in the first place.
It's a no-cost decision.
--Shannon