Illegal questions that pop up in job interviews

When it comes to the process of hiring and getting hired, it's not always what you say, but how you say it.

A good 20 percent of hiring managers say they've asked a question in conducting a job interview only to find out later it was illegal to ask.

That's among the findings of a nationwide survey of more than 2,100 hiring and human resource managers released Thursday by CareerBuilder, which commissioned Harris Poll to conduct the online survey late last year.

"So many people have a hand in hiring these days," Michael Erwin, senior career advisor at CareerBuilder, told CBSMoneyWatch. "You may want to sit down with human resources" to catch up on acceptable questions and how to ask them, said Erwin in advising those readying to conduct interviews.

Conversely, if you're a candidate for employment and are asked a question that seems inappropriate or you know to be illegal, the conversation doesn't need to be confrontational.

"As a job seeker, you don't have to answer every question. You can say 'I'm not comfortable with that,'" Erwin said. "If they press, this might not be the best opportunity for you."

It's OK for an employer to ask a potential employee if they have a criminal record, but it's not OK -- and in fact is against the law -- to ask a prospective hire if they've ever been arrested. It's alright to ask candidates about long-term goals, but it's not to ask when they plan to retire.

Other examples of the nuances between what's acceptable and what's not include location. It's OK to ask someone if they're willing to relocate, but it's not OK to ask where they live because that could be interpreted as a way to discriminate based on their location and is, therefore, illegal.

One-third of those surveyed didn't know the following questions are illegal to ask in a job interview:

• What is your political affiliation?
• What is your race, color or ethnicity?
• How old are you?
• Are you disabled?
• Are you married?
• Do you have children or plan to?
• Are you in debt?
• Do you social drink or smoke?