Everyone knows it's illegal for an employer to discriminate on the basis of race, ethnicity and national origin. But what about an English-speaking candidate with a foreign accent?

The answer is no. Well, maybe un poco.

Dianne Markley, a professor at the University of North Texas at Denton (UNT) whose graduate research focused on how accents affect the hiring process, says it is "almost impossible to speak any language acquired later in life without an accent." A UNT study showed "an incredibly strong statistical correlation between judging someone as cultured, intelligent, competent, etc., and placing them into prestigious jobs," based on the lack of a readily identified accent.

Accents Trigger Emotional Responses

"A professional tries not to let an accent get in the way of hiring decisions," says Victor Arias, comanaging partner of the diversity practice at executive search firm Heidrick & Struggles. "But subtle emotions can come into play, and they may make a difference. Clearly, people make judgments based on accents."

Arias notes that assumptions work two ways: "Not only may someone with a Hispanic accent be deemed ‘less educated,' but someone with a British accent may be seen as ‘more intelligent,' again with no basis." By the same token, Markley says, an Asian accent could be viewed as a plus by a scientific or engineering company. "It's all very situational," she adds.

Worldly or Unrefined?

Someone with a slight accent of any kind might be viewed as more educated or worldly than someone with a thick accent. "I've fallen for that," Arias admits. "I've heard a thick accent and thought, ‘Boy, he hasn't left the neighborhood.' And I've been completely wrong. I've had to slap myself."

An accent, Markley notes, is "a pattern of pronunciation." That is different from whether a person uses language well and forms sentences correctly. "A person can speak flawless English, but an accent causes him or her to be seen as someone who can't do the job," she says.

Strong Accents Can Affect Hiring Chances

Candidates should be hired on their qualifications alone, Markley says -- provided their verbal abilities are appropriate for the job. Unfortunately, "sometimes an accent leads to the perception that that person can't perform this job," she adds. In fact, it is legal to not hire someone whose accent materially affects his ability to perform key aspects of a job.

Markley cites the example of a customer service representative: "That position requires excellent communication skills, and someone who could not be understood well would honestly interrupt the flow of business."

However, Markley emphasizes, "It's not OK to use an accent as a proxy for discrimination based on national origin." For example, a company can't claim a person with a thick Hispanic accent can't communicate with English-speaking customers, while someone with an equally heavy French accent can.

Focus on Clear Speaking Skills

Arias says that while most companies understand the importance of diversity, he knows of no company that addresses the effect of accents on hiring. As a result, every person with hiring responsibility should be aware of the possibility of unconscious bias against speakers with accents.

Markley's advice for job seekers with accents: "First, relax. An accent is part of who you are. It connects you with your family and a particular part of the world. An accent is not a bad thing."

At the same time, "Be careful how you use the English language," Markley cautions. "Be sure to use good grammar. Speak slowly. Don't get frustrated if you have to repeat yourself. There's plenty of stress in job seeking. Don't add more by worrying about your accent."

Carlos Soto, president of the National Hispanic Corporate Council, adds this hint: "Prepare more than anyone else. Practice your answers in English. An accent shouldn't matter, but it does. That's life."