At least 9 claims can be asserted against an employer under FEHA or the Fair Employment and Housing Act. (Govt. Code section 12940.) Let's count:
You can't discriminate.
You must accommodate -- disabilities and religious beliefs, observances and practices.
You can't inquire or require an examination to determine whether a disability or medical condition exists, or the nature of the disability or medical condition, except under certain conditions.
You can't retaliate.
You can't harass ... employees, independent contractors or interns.
You can't fail to take all reasonable steps necessary to prevent discrimination and harassment.
You must explore available reasonable alternative means of accommodating religious beliefs or observances.
You must engage in a timely, good faith, interactive process to determine effective reasonable accommodations.
You cannot test for genetic characteristics.
And don't forget, an employee could sue you because (s)he is in a protected class, or because you believe the employee is in a protected class, or if the employee associates with someone who is in a protected class, or if the employee associates with someone you perceive to be in a protected class. (Govt. Code section 12926(o).)
And do you know all of the protected classes under FEHA? They include race, religious creed, color, national origin, ancestry, physical disability, mental disability, medical condition, genetic information, marital status, sex, gender, gender identity, gender expression, age, sexual orientation, or military and veteran status. (Govt. Code section 12940(a).)
Are you dizzy yet?
So let me ask. Assume an employee sues you for harassment and failure to prevent harassment. After the trial, the jury concludes that there was no harassment. Can the employee still win on failure to prevent harassment? Nope. That's the ruling in Dickson v. Burke Williams, Inc. 2015 Cal.App.Lexis 209. The court held that if harassment or discrimination is not proven, the employee can't win on a claim that the employer failed to take all reasonable steps to prevent harassment or discrimination.
That's the correct decision by the court. If there was no harassment or discrimination how could the employer have failed to prevent it. But don't get too warm and fuzzy. There are still plenty of other ways for a disgruntled employee to sue you.