"It is advisable for an employer to keep records of all complaints of harassment."
But, establishing patterns of negative behavior is not just the responsibility of the victim of harassment, retaliation, etc. The employer is also obligated to examine the pattern behavior of employees. When it comes to patterns of negative behavior, the EEOC says:
“Reasonable preventive measures include screening applicants for supervisory jobs to see if any have a record of engaging in harassment. If so, it may be necessary for the employer to reject a candidate on that basis or to take additional steps to prevent harassment by that individual…it is advisable for an employer to keep records of all complaints of harassment. Without such records, the employer could be unaware of a pattern of harassment by the same individual. Such a pattern would be relevant to credibility assessments and disciplinary measures.”
This all goes to show how important it is to look for prior bad acts by a harasser. But, at the same time, it shows how important it is to notify your employer/make a formal complaint of harassment, if you believe you are being subjected to a hostile and offensive work environment.
Think of it this way…if you suffer in silence, you embolden your enemies—as our President, George W. Bush, is fond of saying.
By filing a complaint against your harasser, you help to create a history of your harasser behaving in an illegal manner. If your harasser has already been on the receiving end of harassment complaints, their record of this illegal behavior will be extended to the present—as opposed to possibly years ago.
Just the fact that you made a complaint can go a long way towards helping another employee, who may find that they have the same problem with this same employee—in the future. It’s up to each of us to hold racist employees, harassers, etc. to account.
Still, even without complaints, employers are responsible for any illegal behavior that was so prevalent that members of authority/management had to have known the illegal abuse was happening!