I’ve been reading a lot about jury nullification, and I get that jurors have the power to acquit someone even if the law technically says they’re guilty. But what I don’t get is—why is this something that exists, yet courts don’t allow it to be talked about during a trial?

If it’s a legitimate part of the legal system, why is it treated like a secret? Would a juror get in trouble for mentioning it during deliberations? And what would happen if someone brought it up during jury selection?

I’m just curious how this all works in practice. If jurors can ultimately do whatever they want, what stops them from using nullification all the time?