Generally, thorough documentation and communication can go a long way toward reducing an employer's exposure to liability for wrongful termination. An employer should keep a detailed record of any and all problems relating to an employee's performance, including dates and times, and communicate the problems and potential remedies to the affected employees. At the time of termination, the employer should meet with the employee and provide a letter stating the reasons for the termination and the date on which it goes into effect.
In California, an employer may not terminate an employee on the basis of age, race, sex, religion, national origin, disability, pregnancy, or sexual orientation. Furthermore, it is unlawful to terminate an employee for refusing to break the law, for taking leave under the Family and Medical Leave Act, or for a reason not contained in the employment contract (if there is one). It is also unlawful to fire an employee in retaliation for filing a discrimination or safety claim. Finally, if the company has a stated policy or procedure with respect to employee disciplinary action or termination, it must not fire someone without following that policy or procedure.
Taking disciplinary action or terminating an employee can be an extremely delicate matter. Consulting with an experienced employment law attorney prior to taking any action can considerably reduce the risk of potential liability.