Illegal: Are you a U.S. citizen? Where were your parents born? What is your native language?
Legal: Are you authorized to work in the U.S.? What languages do you speak?
Illegal: Are you married? Do you have, or plan to have children? Have you ever been divorced? What do you do for child care?
Legal: Are you willing to relocate? Are you willing and able to put in the amount of overtime and/or travel the position requires?
Illegal: Are you a U.S. citizen? What is your religion? Are you practicing?
Legal: Does your religious affiliation, if any, interfere with your working in this position?
Illegal: How old are you?
Legal: Are you over 18?
The very first interview question I ask is "Tell me about yourself".