An affirmative defense is a type of legal defense that can be raised by a defendant in support of his or her side of a case. As a general rule, through an affirmative defense, a defendant presents additional facts that serve to diminish the civil claims or criminal charges being brought against him or her. This is done without arguing against any pertinent elements of the alleged crime. In other words, the defendant agrees with the facts presented by the plaintiff or prosecution but also introduces additional facts that mitigate the defendant's liability or culpability.
For example, suppose that a plaintiff sues a defendant for damages relating to a car accident. Specifically, the plaintiff alleges that the defendant struck the back of the plaintiff’s car, resulting in damages to the car’s bumper. Without disagreeing with this fact, the defendant may raise an affirmative defense by arguing that the plaintiff contributed to the accident. The defendant may claim that the plaintiff slammed on the car brakes, thereby causing the defendant to rear-end the plaintiff’s car.
Affirmative defenses are used primarily in common law countries, and they can be raised in both civil and criminal cases. For example, in a civil lawsuit, suppose that an employee is suing an employer for gender discrimination. Without denying the charges that have been brought, the employer may raise one or more civil affirmative defenses. The employer may state that it has gender discrimination policies and procedures in place to ensure that harassment does not occur in the workplace. Additionally, the employer may claim that the company took measures to address the harassment once it was reported to the human resources department.
Affirmative defenses may also be raised by defendants in criminal cases. For instance, suppose that a woman is on trial for murdering her husband. Without disagreeing that she murdered her husband, the woman may claim self-defense. She may state that her husband attacked her, and she had to kill him in order to protect herself from harm. Self-defense is a common affirmative defense, and is frequently used to support exonerating a defendant.
The effect of most affirmative defenses is to either reduce - or excuse altogether - a defendant’s liability in a civil case or culpability in a criminal case. Exoneration or liability or culpability occurs even if a plaintiff is able to show that the facts supporting the plaintiff’s case are true. If an affirmative defense is sought in a case, a judge typically instructs the jury on the specific defense theory at hand. The jury must then take that defense into consideration when rendering a verdict in the case.