It's natural for job candidates to be nervous going into the interview process. But if you're fairly new to conducting interviews on the employer side, you might have your share of jitters as well -- especially in light of the fact that asking the wrong questions could subject your business to a lawsuit.

In case you're not well versed in discrimination laws, here's a quick primer: You're not allowed to discriminate against employees based on race, color, religion, gender, and national origin. When interviewing candidates, you'll need to be sensitive to these guidelines to avoid inadvertently breaking the law. With that in mind, here are a few questions to avoid at all costs.

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1. How old are you?

Since age is a protected class from an employment discrimination standpoint, you can't ask a job candidate his or her age directly. What you can ask, however, is for a number of years of experience in the field to get a sense of his or her qualifications. Furthermore, while you can't ask candidates what year they graduated high school or college, you are entitled to know how much education they completed. In other words, you can ask if a candidate has a college degree, but not what graduating class he or she was part of.

2. Do you have religious constraints?

Since religion is another protected class, you can't directly ask candidates what religion, if any, they practice, or what implications it might have on their work lives. But you can ask candidates if they're available to work after-hours or on weekends if that's part of the job.

3. Are you pregnant or planning to have children?

This is another question you want to stay away from, because you can't base a hiring decision on a woman's pregnancy status or desire to procreate in the future. That said, you can ask candidates if they're physically able to perform all of the functions pertaining to the job at hand. For example, if the job involves heavy lifting and you suspect that an applicant is pregnant, you can't ask whether she's expecting, but you can verify that she can do the work that comes with the job.

4. Do you have any disabilities?

The Americans with Disabilities Act prohibits employers from discriminating against job candidates with disabilities. That said, as is the case with a pregnant applicant, you are allowed to ask if the applicant in question is able to perform the job functions necessary for the role at hand.

5. Are you a U.S. citizen?

As an employer, it's your duty to verify that anyone you hire is legally allowed to work in the U.S. But that doesn't mean you can only hire U.S. citizens, and asking a job candidate during an interview whether he or she is indeed a citizen is a major no-no. That said, you are allowed to ask candidates whether they're authorized to work in the U.S., and once an offer of employment is extended, you're actually required to verify that.

The last thing you want to do as the person conducting a job interview is slip up on one of these questions and be accused of discrimination, even if that wasn't your intent. Therefore, as a general rule, err on the side of caution when meeting with candidates. An even better bet might be to hire a human resource or employment law consultant who can develop guidelines for your business that help you steer clear of these and other potential land mines. A modest investment could save you a world of hassle in the long run.

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