Just because an employee urges you to investigate alleged discrimination, don’t assume you have to treat that person with kid gloves. If it turns out that the complainer was actually the one causing the problems, you can—and should—take action.
Recent case: Anthony Keith, a black male, complained about race bias in promotions and provided the names of other black workers who could back him up. But those employees didn’t back him up. In fact, they said Keith had been sexually harassing them. After an investigation, the company fired Keith. He sued, claiming retaliation for his race-bias complaint. The court tossed out his case. (Keith v. MGA Inc., No. 06-12803, 11th Cir., 2006)
Bottom line: Employees may think they’re protected from any discipline if they get a complaint on record. Not true!