Wrongful Termination
In the United States, most employers hire employees "at-will," meaning that both the employer and employee may terminate the employment relationship at any time. Employees can quit at any time. Likewise, employers may terminate an employee at any time unless the parties signed an employment contract that sets the duration of employment or the employer seeks to terminate the employee for an illegal cause.
Breach of Contract
Companies often sign contracts with their employees to define the terms of employment. Usually, the contract will state that the employment is at will and that either party may terminate the agreement at any time. However, in some instances, the parties may sign a contract that expressly states the duration of employment and prohibits the employer from terminating the employee during the employment period absent "good cause." Usually, the contract will specify what acts constitute good cause.
Additionally, some states will find an implied contract of continued employment if the employer documented that it will only terminate the employee for good cause. Possible documents that may contain such provisions include an employer policy manual or an employee handbook that outlines the company's discipline or termination protocol.
Breach of Good Faith and Fair Dealing
Some states recognize an implied covenant of good faith and fair dealing in employment relationships. This covenant requires employers to treat their employees fairly. For example, an employer may breach this covenant if it terminates an employee right before a benefit would vest, just to avoid paying a bonus.
Constructive Discharge
A constructive discharge occurs when an employee resigns from a job because the employer has made the working conditions intolerable or permitted such conditions to exist, and a reasonable employee would also have quit when faced with the same conditions. Employees usually face a difficult time proving that a constructive discharge occurred.
Defamation of Character
An employee has been wrongfully terminated if an employer intentionally defamed him to justify his termination, such as falsely accusing an employee of stealing as an excuse to fire him.