Most “At Will” employers won’t give you a reason when they fire you. Once they give you a reason, they have to justify it.
There are protected classes. This was taken from a quick google search of protected classes. Some may only apply to California:
Protected Classes
Various federal and state Equal Employment Opportunity (DFEH) laws govern discrimination and harassment. The various laws create what are known as “protected classes.” If a person is in a “protected class” and is treated differently because of his or her membership in that class, then the treatment violates these laws. “Protected classes” created by these laws include gender, race/color, national origin, religion, age and disability. It also prohibits retaliation.
Title VII of the Civil Rights Act of 1964 prohibits discrimination in employment on the basis of race/color, gender, national origin and religion. Sexual harassment is a form of gender discrimination. Harassment on the basis of race/color, national origin or religion is also a prohibited form of discrimination under the act.
The Americans with Disability Act (ADA) prohibits employment discrimination and harassment on the basis of the disability.
The Age Discrimination in Employment Act (ADEA) prohibits age discrimination in employment. It also prohibits harassment on the basis of age.
In California, the Department of Fair Employment and Housing (FEHA) protects the people of California from unlawful discrimination in employment, housing and public accommodations, and from the perpetration of such acts of hate violence.
The California Fair Employment and Housing Act (FEHA) provides protection from harassment or discrimination in employment because of age, ancestry, color, religious creed, denial of family and medical care leave, disability (mental and physical) including HIV and AIDS, marital status, medical condition, national origin, race, religion, sex and sexual orientation.
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