My mother is a naturalized U.S. citizen since 1991 and has on occasion been asked to provide her U.S. passport or Certificate of Citizenship in addition to a drivers license and social security card. This seems like an unnecessary step to me as I've (I am a U.S. born citizen) never been asked for anything more than a Driver's License and Social Security. Does anyone know if this is standard procedure for foreign born citizens? It seems kind of discriminatory to me but maybe I'm missing some important reason for this. Thanks in advance for your replies.