In the U.S., illegal interview questions are those that discriminate against you on the basis of
• Age
• Color
• Disability
• Gender
• National origin
• Race
• Religion or Creed
Although they're coined illegal interview questions, the act of asking them is not necessarily illegal. For example, according to the Equal Employment Opportunity Commission (EEOC), the Age Discrimination in Employment Act of 1967 (ADEA) does not make it illegal for an employer to ask an applicant's age or date of birth. But the ADEA does make it illegal to deny employment, solely because the applicant is 40 years of age or older. So, while asking the question isn't illegal, a discriminatory motive behind it is, when it ultimately denies employment.
Unknown motive is what makes any question with discriminatory implications an inappropriate question for interviewers to ask. Since you can't read an interviewer's mind, it might lead you to believe that you weren't hired because of discrimination, whether or not it's true. As a result, you might file a discrimination charge. So, smart interviewers avoid such questions in the first place, illegal to ask or not.
Still, there are those who ask anyway, either intentionally or ignorantly. That's what you have to decide before answering or filing a discrimination charge. For example, if you're over 40 and an interviewer asks when you graduated from college, is he or she intentionally discriminating against your age or just trying to be friendly? Does the interviewer have malicious intent or is he or she simply naive of the implications?
Marital Status
Inappropriate:
Are you married?
Is this your maiden or married name?
With whom do you live?
Appropriate:
After hiring, marital status on tax and insurance forms
Parental Status
Inappropriate:
How many kids do you have?
Do you plan to have children?
Are you pregnant?
Appropriate:
After hiring, asking for dependent information on tax and insurance forms
Age
Inappropriate:
How old are you?
What year were you born?
When did you graduate from high school?
Appropriate:
Before hiring, asking if you are over the legal minimum age for the hours or working conditions, in compliance with state or Federal labor laws. After hiring, verifying legal minimum age with a birth certificate or other ID, and asking age on insurance forms
National Origin
Inappropriate:
Where were you born?
Where are your parents from?
What's your heritage?
Appropriate:
Verifying legal U.S. residence or work visa status
Race or Skin Color
Inappropriate:
What race are you?
Are you a member of a minority group?
Appropriate:
Generally indicate equal opportunity employment. Asking race only as required for affirmative-action programs
Religion or Creed
Inappropriate:
What religion are you?
Which religious holidays will you be taking off from work?
Do you attend church regularly?
Appropriate:
Contact religious or other organizations related to your beliefs, that you list as employers or references
Criminal Record
Inappropriate:
Have you ever been arrested?
Have you ever spent a night in jail?
Appropriate:
Questions about convictions by civil or military courts, if accompanied by a disclaimer that answers will not necessarily cause loss of job opportunity. Specific convictions, if related to fitness to perform the job, and the most-recent conviction (or prison release date) is within 7 years of job application date. Generally, employers can ask only about convictions and not arrests, except for law-enforcement and security-clearance agencies.
Disability
Inappropriate:
Do you have any disabilities?
What's your medical history?
How does your condition affect your abilities?
Appropriate:
Ask if you can perform specific duties of the job. After hiring, ask about medical history on insurance forms
Below are tips for answering illegal interview questions.
Just Answer
If the question doesn't bother you, just answer it. (It's not illegal to answer.) But proceed with caution, as it might bite you later. You might not get the job, even if it's illegal to deny you employment.
Refuse to Answer
Point out that it's not an appropriate job interview question and you don't feel comfortable answering it. (Avoid the term illegal interview question since it might not be, at least not yet.) That's your right. But that might bite you later too.
Tactfully Sidestep
Assess the motive behind the question. If you don't think it was malicious and you really want the job, then put it back on the interviewer or answer indirectly. This might make the interviewer realize that he or she asked an inappropriate question. For example, if an interviewer asks about your
Personal life, you might respond with, "I prefer to keep personal and business matters separate."
Children, your reply might be, "Are you concerned that I won't be able to travel or work overtime?"
Disability, you might say something like, "If you're concerned that I won't be able to perform the duties of the job, I'm sure I can."
Country of origin, you could say, "If you're going to ask next whether or not I'm authorized to work in the USA, I am."
From:
http://jobsearchtech.about.com/library/weekly/aa022403.htm