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Definition: Self-Defense from The SAGE Glossary of the Social and Behavioral Sciences

A justification defense for committing a criminal act where it is argued that another reasonable person would have acted in the same way. The defendant must have acted with the realistic belief that he or she was in imminent danger of harm or death and had no other viable way to escape the situation.


Summary Article: Self-Defense from Encyclopedia of Interpersonal Violence

Self-defense is the legal right of a person to defend against unlawful force. Generally, the term does not apply to the defense of others or the defense of property. Self-defense is a private defense in which an individual, rather than the state, lawfully engages in protective actions against threat by another person. Representing one of the oldest defenses in criminal law, self-defense may also be a defense to some civil claims.

Self-defense law applies when one uses force under the reasonable belief that force is necessary to protect oneself against the immediate use of unlawful force by another. Force is considered unlawful when it would constitute a civil wrong or a criminal offense. A person must not use greater force than appears reasonably necessary in the circumstances, meaning that the force used in self-defense must be proportional to the severity of the threat posed. Timing is also crucial; self-defense is justified only when the threat of force is imminent.

Additional requirements apply when the use of force to protect oneself involves deadly force. Deadly force is permissible only when one reasonably believes deadly force is necessary to protect oneself against the immediate use by another of unlawful deadly force. Many laws also require that one retreat, if possible, before using deadly force in response to the immediate threat. Some jurisdictions do not require retreat if threatened in one’s own home, while others do if the deadly threat is from a cohabitant.

In homicide cases, whether the defendant’s actions constitute a total defense to any criminal charge at all or whether it merely mitigates his or her criminal responsibility depends, in some jurisdictions, on a showing of either perfect self-defense or imperfect self-defense. Perfect self-defense is established if the defendant believed that killing the alleged attacker was reasonable and necessary under the circumstances, and the fact finder agrees that a hypotheti-cally reasonable person would have done the same. Perfect self-defense, if proven, would be a complete defense to the crime. On the other hand, in imperfect self-defense, the fact finder rules that, while the defendant believed that killing the alleged attacker was reasonable and necessary, the defendant used excessive force. Imperfect self-defense is only a partial justification and generally would reduce a murder charge to the less serious crime of manslaughter.

Critics claim self-defense law is historically based on a gendered perspective. The traditional model of self-defense assumed a confrontation between two adult males, with the expectation that a male would draw back if able and would only use the amount of force required in the situation. Thus, this argument posits that the self-defense model fails to accommodate the experiences of women, particularly with respect to intimate, yet violent, relationships, where there often are size and strength differences between the two individuals and retreat may be difficult, particularly when they reside in the same abode.

    See also
  • Battered Women’s Justice Project

Further Readings
  • Rosen, R. A. On self-defense, imminence, and women who kill their batterers. North Carolina Law Review, 77, (1993). 371-411.
  • Sangero, B. A new defense for self-defense. Buffalo Criminal Law Review, 9, (2006). 475-559.
  • Melissa Hamilton
    Copyright © 2008 by SAGE Publications, Inc.

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