Can a co-worker, supervisor, or manager be held personally liable for violation of the anti-discrimination statutes?
The long answer is that under the federal statutes (Title VII, ADA, ADEA, etc.) the company is the proper defendant. Under California law (the Fair Employment and Housing Act, etc.), there is a difference between discrimination (personnel actions such as hiring, firing, promotion, etc.) in which there is no individual liability and retaliation or harassment (going beyond the decision-making role of a supervisor such as making racist or sexist remarks or creating a work environment which is hostile to a protected group) where individuals can be held individually accountable. The short answer is that in California it’s an unsettled point of law and you need to see an attorney if this is an issue in your case.