If ONE juror stood firm with a nullification verdict over the other 11 .. guilty verdicts ... nullification wins ?
Typically the jury must be unanimous. So, if one juror decides that the law is unjust, unconstitutional, etc., he or she can vote to exonerate. You don’t have to give a reason as a juror, you can just vote not guilty and let the world wonder why you did it.
But, and this is the important part, you SHOULD NOT say nullification is your reason to vote not-guilty. Otherwise the judge might (and they sometimes do) remove that juror and replace him with an alternate.
Just say "The prosecution has not proved their case beyond my reasonable doubt". And nothing more.
It is our system, and it has been thus for over 300 years, and you don’t seem to understand it... Do you wonder why?