Self-Defense

The protection of one's person or property against some injury attempted by another.

Self-defense is a defense to certain criminal charges as well as to some civil claims. Under both CRIMINAL LAW and TORT LAW, self-defense is commonly asserted in cases of HOMICIDE, ASSAULT AND BATTERY, and other crimes involving the attempted use of violence against an individual. Statutory and case law governing self-defense is generally the same in tort and criminal law.

A person claiming self-defense must prove at trial that the self-defense was justified. Generally a person may use reasonable force when it appears reasonably necessary to prevent an impending injury. A person using force in self-defense should use only so much force as is required to repel the attack. Nondeadly force can be used to repel either a nondeadly attack or a deadly attack. DEADLY FORCE may be used to fend off an attacker who is using deadly force but may not be used to repel an attacker who is not using deadly force.

In some cases, before using force that is likely to cause death or serious bodily harm to the aggressor, a person who is under attack should attempt to retreat or escape, but only if an exit is reasonably possible. Courts have held, however, that a person is not required to flee from his own home, the fenced ground surrounding the home, his place of business, or his automobile.

A person who is the initial aggressor in a physical encounter may be able to claim self-defense if the tables turn in the course of the fight. Generally a person who was the aggressor may use nondeadly force if the victim resumes fighting after the original fight ended. If the original aggressor attacked with nondeadly force and was met with deadly force in return, the aggressor may respond with deadly force.

Courts and tribunals have historically accepted self-defense as a defense to a legal action. As a matter of public policy, the physical force or violence associated with self-defense is considered an acceptable response to aggression.

The same values that underpin self-defense support the defense of property. Generally a person has greater latitude in using physical force in the defense of her dwelling than in the defense of other property. In most jurisdictions deadly force is justified if a person unlawfully enters onto property and the property owner reasonably believes that the trespasser is about to commit a felony or do harm to a person on the premises. Deadly force may also be justified to prevent a BURGLARY if the property owner reasonably believes the burglar intends to kill or seriously injure a person on the premises. However, a person may not, for example, rig a door handle so that any person who enters the dwelling is automatically shot by a gun. (Katko v. Briney, 183 N.W.2d 657 [Iowa 1971]).

Use of deadly force is never justified to protect PERSONAL PROPERTY other than a dwelling. For example, a person would not be justified in shooting a person who is taking an automobile, no matter how expensive. Reasonable nondeadly force may be used to protect such personal property.

A person may use force to defend a third person from attack. If the defender is mistaken, however, and the third party does not need assistance, most jurisdictions hold that the defender may be held liable in civil court for injuries inflicted on the supposed attacker. In criminal cases a defendant would be relieved of liability if she proved she had made a reasonable mistake.

A defendant who successfully invokes self-defense may be found not guilty or not liable. If the defendant's self-defense was imperfect, the self-defense may only reduce the defendant's liability. Imperfect self-defense is self-defense that was arguably necessary but somehow unreasonable. For example, if a person had a GOOD FAITH belief that deadly force was necessary to repel an attack, but that belief was unreasonable, the defendant would have a claim of imperfect self-defense. In some jurisdictions, the successful invocation of such a defense reduces a murder charge to MANSLAUGHTER. Most jurisdictions do not recognize imperfect self-defense.