In California, it is against the law for an employer to discriminate against a job applicant or employer because of their national origin, citizenship, or immigration status. Such discrimination is regulated by Title VII, which applies to employers with 15 or more employees, and the Immigration Reform and Control Act (IRCA), which applies to employers with four or more employees. While IRCA was passed to resolve various immigration-related issues, it includes a provision that makes it unlawful for employers to hire or fire an employee based on citizenship or immigration status (not including unauthorized aliens).
Discrimination lawsuits based on national origin, immigration status, and citizenship are becoming increasingly common. As an employer, you are not allowed to treat an employee adversely with any consideration of his or her national origin, citizenship or immigration status in relationship to any significant aspect of employment.