Legal Question in Discrimination Law in California

No.

Police have NO legal obligation to take any particular action, investigate anything, arrest anyone, file reports, etc. They can not be sued for any failure to act. They are there to protect 'society', not you specifically. For example, calling 911 does not guarantee police response, it is merely a desperate plea for help. That is why the old self defense saying, "better a gun in the hand, than a cop on the phone". The other old saying that applies is, "when every second counts, help from 911 is only minutes away".