Courts can be against it all they want, it is still legal and well within a juror's rights. I'd never expect a judge or attorney to raise it as an option, but at the end of the day it is.

Jury selection throws a wrench in the system, lawyers have a chance to ask questions under oath and get rid of jurors for most any reason. As i understand it, its pretty common for them to try to ferret out anyone that may go the nullification route.