Employees who don’t belong to the same protected class as one that is the subject of alleged harassment can’t successfully sue over that harassment except in limited circumstances.
Certainly try to stop all harassment based on protected class membership, but don’t worry too much that any employee can sue.
Recent case: Matthew Thompson, who is white, was a police officer with a long history of substandard performance. When he was finally disciplined for his shortcomings, he fired back with a claim alleging a racially hostile work environment. He said his supervisors had made racially bigoted comments about black officers.
But the court said that—absent solid evidence that Thompson himself was targeted for retaliation for associating with the black officers he was championing—he had no standing to sue. (Thompson v. City of Monrovia, No. B216252, Court of Appeal of California, 2nd District, 2010)