A defense available in employment discrimination cases that can be used to limit the employer's exposure to damages (for example, by cutting off back pay), but not to avoid liability entirely. An employer can assert this defense if it learns about employee wrongdoing after it took adverse employment action against the employee (such as discharge), and that employee wrongdoing would have caused the employer to lawfully take adverse employment action if the employer had known about the wrongdoing earlier. To use this defense, the employer must prove that the employee misconduct was so severe that the employer in fact would have taken the adverse employment action against the employee had it known of the misconduct. Unlike mixed motive cases, however, the employer does not have to prove that the employee misconduct was a motivating factor in the adverse employment action. (See McKennon v. Nashville Banner Publ'g Co., 513 U.S. 352 (1995).)

After-acquired evidence may be learned through discovery in the case and commonly includes evidence that the employee:

For more information on anti-discrimination laws, including theories of liability and available defenses, see Practice Notes: