When employee complains about bias, always investigate before taking any adverse action.

Nothing will doom an employer's case quite as fast as firing a worker right after she has filed an internal discrimination complaint that was ignored. That virtually guarantees the court will believe there might be some connection between the employee's complaint and her firing.

Recent case: Shawn, a black woman, worked as a buyer for Wesco Aircraft for about 18 months. She was the only black employee in her department; her two supervisors were both white women.

Almost from the beginning, Shawn believed she was being held to a higher standard than her fellow buyers who were white. She believed she had stricter deadlines and a heavier workload. She also observed that she was reprimanded for missing deadlines, while her white co-workers were not. Plus, she alleged that she was written up for singing at work even though her white co-worker, who sang with her, was not reprimanded.

Shawn filed a...