Being that it's a constitutional amendment, it would difficult for it to be unconstitutional. It is possible but I believe it would have to be found to have either been created/passed inappropriately or be itself a violation of some other protected class type law.
Still happily answering to the call-sign Peetza.
You do not HAVE a soul. You ARE a soul. You HAVE a body.
He is no fool who gives what he can not keep to gain what he can not lose.
-Jim Eliott, paraphrasing Philip Henry.