for the OP:
Would you join the Hispanic Law Students Organization (or whatever) and tell all of them that you are indeed an hispanic person?
and joining organizations is an important tets for a real urm?
I think SC's point was that if the OP wouldn't tell actual hispanic people that he/she is hispanic, then he/she should not claim minority status on his applications.
Oh, and I just wanted to add that I would find claiming URM status to be morally reprehensible.