Thank you very much for your reply.
There is good news and bad news concerning your situation, and I hope that you don't mind if I start with the bad.
The bad news is that workplace "harassment" is generally not illegal unless physical threats are made or the harassment relates to a legally protected trait, such as race, gender, or religion. So, while it is against the law to shout racial slurs at someone or to threaten to bring a gun to work, it is not illegal to be generally rude, mean or hostile.
If physical threats had been made, you could have also applied for a restraining order, with which your employer would have a legal duty to comply, and which then would likely trigger your transfer to another department. However, as no physical violence was threatened and such threats are a prerequisite to a restraining order, this unfortunately cannot serve as a basis for a transfer demand.
The above is the bad news. The good news is that you may have one argument that you can leverage into a transfer. That argument would be derived from California's Fair Employment & Housing Act, which requires employers to "reasonably accommodate" employees suffering from "disabilities" (defined as health conditions that impair a major life function.)
If you can argue that your mental condition qualifies as a disorder that "impairs a major life function" -- and you likely can if a doctor warranted it was serious enough for a Xanax prescription, you can argue that a "reasonable accommodation" in your circumstance is a transfer away from the manager who has caused this condition to develop and will only continue to make it worse.
If your employer refuses to provide a transfer as a reasonable accommodation, then you may have grounds to sue for a FEHA violation. Again, all of this assumes that your mental condition qualifies as a condition that "impairs a major life function," but as noted, it likely would satisfy this definition if your condition warranted prescription drugs.
This letter demanding a transfer as a reasonable accommodation pursuant to FEHA can be drafted by your self but is best drafted and sent by an attorney, as your employer will be much more inclined to give it substantial weight and consideration. To locate a local employment law attorney who can assist you with drafting this demand for accommodations, see here: http://www.cela.org/?page=4
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