9 things hiring managers should never ask about in a job interview

You may think asking a job candidate whether they have kids is a totally innocuous icebreaker, but it's one of many topics best left alone during a job interview.

While very few specific interview questions are by themselves illegal to ask, Laura Davis, an associate professor with the Department of Finance and Legal Studies at Bloomsburg University of Pennsylvania, explains in the Journal of Employment and Labor Law that some questions may be used as evidence of discrimination and, so, are ill-advised to ask.

"Since it is reasonable to assume that all questions in an interview are asked for some purpose and that hiring decisions are made on the basis of the answers given, any question asked during the interview can be used as circumstantial evidence of a prohibited discriminatory motive," she says.

In the US, certain personal characteristics are part of a protected class and can't be targeted for discrimination thanks to certain federal or state anti-discrimination laws.

"Even without any intentional ill will, employers who have knowledge concerning the protected class status of applicants may make biased assumptions about their capabilities or work habits," Davis says.

She suggests the best approach to take while conducting an interview is focusing on the specific criteria needed to perform the job. She says this will help you find the most able employees and protect you from being found to be discriminatory.

Here are some topics you're better off not bringing to the table:

Aaron Taube contributed to an earlier version of this article.