The California Fair Employment and Housing Act is one of the most powerful anti-retaliation laws in the United States. These laws define retaliation broadly so that any kind of adverse action (demotion, firing, transfer, schedule change, loss of company car etc.) by a company can amount to retaliation. Also, the underlying conduct that sparks the complaint does not have to be illegal so long as the complaining employee had a good faith belief that it was illegal.