I manage a customer service call center at a local bank with a dozen branches. We have an employee who is wonderful in every way, but our customers complain that they can't understand him. He is from Egypt; he knows English well, but he has a very heavy accent. I need to address these complaints, but it doesn't seem fair to discipline him just because of the way he sounds. And, I may need to transfer him to a position that doesn't require him to interface with customers by phone (people seem to have an easier time understanding him in person). Am I going to get in trouble for discriminating?
You're right to be concerned. Accent and language fluency are both very closely associated with national origin, a protected characteristic under discrimination laws. Employers can't adopt blanket rules that they won't hire anyone who speaks accented English, or that no employee who speaks with an accent can work in customer-facing positions. And of course, it would be illegal for an employer to single out accents from particular countries or regions for disapproval.
On the other hand, English communication skills are a job requirement for many positions. If an employee's accent substantially affects his or her ability to communicate with, and be understood by, customers, that's an objective and valid basis for job decisions. In this situation, your customers cannot understand the person your company has designated to assist them with their problems. That means you need to make a change.
As you point out, there's no reason to discipline the employee. Although customer complaints sometimes mean an employee needs to improve, it doesn't sound like that's the case here. There is simply a poor fit between the job's requirements and the employee's skills. Finding a comparable position that doesn't require telephonic communication with customers is the best solution.