Although most US employers have at-will employment contracts that allow them to terminate anyone without giving valid reasons, they can still be sued for wrongful termination for the following reasons.
According to federal law, it is unlawful to terminate an employee based on his or her gender, pregnancy, race, color, national origin, religion, age, and disability. Meanwhile, some states, including California, have broader laws that prohibit discrimination based on sexual orientation.
It is unlawful to terminate employees for reporting to authorities some illegal activities of their companies, employment discrimination in their workplace, and violations of their employers such as failing to provide a safe work condition.
According to federal Immigration Reform and Control Act (IRCA), it is unlawful to terminate employees based on their alien status, unless they are illegal workers.
According to federal Employee Polygraph Protection Act, employers cannot terminate a worker who refuses to take a lie detector test or undergo tests to any devices such as voice stress analyzers, psychological stress evaluators, polygraphs, and deceptographs.
It is unlawful to terminate a worker in violation of public policy such as: