[33girl]

Goat Brothers and Loose Change were books about, respectively, brothers of a fraternity and sisters of a Jewish sorority at Berkeley in the early 1960s. It's mentioned that only 3 sororities on campus accept Jewish women, and that there are 4 fraternities that still have "racial or creedal restrictions. "

But in answer to your question, I don't think there actually is such a rule passed by the NPC - that would be intruding on membership selection which is not what NPC is for. About the only things they agreed on were that members have to be female students of the college where the chapter is designated to exist. The sororities themselves are the ones who removed the religious clauses, probably because they realized it was hindering their progress. I think this no double discrimination business is solely a creation of your school.