Self Defense in the United States

Law of Self Defense


This entry tries to explain the legal principles and the processes involved in the legal system’s approach to a deadly force incident. The entry, then, walks the reader of this legal Ecyclopedia through each of the core elements of a self-defense claim.

There are different contexts for the use of force. Some books explain – in some detail, see biography below – how to interact with the police following a use of force incident.

Self defense is also linked to the framework for a legally-sound defense strategy.

The state´s platforms also lays out and discusses, in relation to self defense, the controlling statutes and case law for each state.

Self-defense Definition

The protection by force of one’s person or property from unlawful injury. The force used must be no more than is reasonably necessary to repel the threatened injury, and must be proportioned to the nature of the injury apprehended. Thus, an assault with the hand cannot be repelled by the use of a deadly weapon. (…). As a general rule, an assault threatening death or serious bodily injury, the infliction of which would amount to a felony, may be resisted to the taking of life (…), but not an assault which is but a misdemeanor (…). Unlawful injury to property may be resisted by force short of the taking of life (…), but the taking of life in defense of property is only justifiable when it is necessary in order to prevent a felony attempted by violence or surprise, as burglary, robbery, or arson (…), but not secret felonies, such as larceny (…). (1)

In crminal law, in the United States, self-defense is an affirmative defense that is used to justify the use of force to protect oneself from an attempted injury by another person.

In internet law, the digital self-defense is the use of self-defense strategies by Internet users to ensure digital security; that is to say, the protection of confidential personal electronic data.

Second Amendment

This entry covers, among other, the issues of legislating away a state’s right to self-defense. Academics have come to call this theory “the collective rights theory”, with a collective rights theory of the Second Amendment.

Right of self-defense

The right of self-defense is the right for persons to use reasonable force or defensive force, for the purpose of defending one’s own life or the lives of other people. In many U.S. states, the right of self-defense is mostly governed by case law, but there are also, in some cases (such as in the case of Maryland) a statute.

Castle Doctrine

An exception to a rule in place in some jurisdictions that requires a defendant to retreat before using deadly force in self-defense. Read more here about what the castle exception states.

Justifiable Homicide

An accidental shooting, a killing in the course of self-defense, or a death that results from the necessary actions of a police officer, would all be on grounds of justifialbe homicide. All homicide is murder, as some killings are manslaughter, and some are lawful, such as when justified by an affirmative defense, like insanity or self-defense.

Affirmative Defense

Self defense, entrapment, insanity, and necessity are some examples of affirmative defenses. See, e.g. Beach v. Ocwen Fed. Bank, 523 U.S. 410 (1998)

Insanity defense

The insanity defense is traditionally classified as an excuse defense, in contrast with justification defenses like self-defense.

Imperfect self-defense

Imperfect self-defense is a common law doctrine recognized by some jurisdictions whereby a defendant may mitigate punishment or sentencing.

Abuse Excuse

Abuse Excuse is a self-defense claim that a defendant is incapable of distinguishing between right and wrong or of controlling his or her impulses.

Self-Defense in Homicide Cases

This section examines the Self-Defense in Homicide Cases subject in its related phase of trial. In some cases, other key elements related to trials, such as personal injury, business, and criminal litigation, are also addressed.



This definition of Self-defense is based on the The Cyclopedic Law Dictionary

See Also

Further Reading (Books)

  • The Law of Self Defense: The Indispensable Guide to the Armed Citizen (2016), by Andrew F. Branca
  • Information about Self Defense in the Gale Encyclopedia of American Law
  • Deadly Force: Understanding Your Right to Self Defense, by Massad Ayoob
  • Gun Digest Book of Concealed Carry, by Massad Ayoob
  • Surviving a Mass Killer Rampage: When Seconds Count, Police Are Still Minutes Away, by Chris Bird
  • In the Gravest Extreme: The Role of the Firearm in Personal Protection, by Massad F. Ayoob Gunfight! An Integrated Approach to Shooting and Fighting in Close Quarters, by Richard Nance
  • Combat Shooting with Massad Ayoob, by Massad Ayoob

Further Reading (Articles)

Self-Defense in International Law and Rights of Persons, Ethics & International Affairs; April 1, 2004; Teson, Fernando R.

Self-Defense Education: Five Steps for Developing Awareness and Prevention Tactics, JOPERD–The Journal of Physical Education, Recreation & Dance; August 1, 2010; Banks, Aaron L.

Self-defense profits! Increase your sales with a product checklist and a solid game plan!, Shooting Industry; May 1, 2004; Connor, John

Self-defense unleashed! No season on sales, no limit on profits!, Shooting Industry; February 1, 2007; Morrison, John

War and Self-Defense, Ethics & International Affairs; April 1, 2004; Rodin, David

Medical Self-Defense, Prohibited Experimental Therapies, and Payment for Organs, Harvard Law Review; May 1, 2007; Volokh, Eugene

SELF-DEFENSE SALES, Shooting Industry; February 1, 2008; Morrison, John

SELF-DEFENSE UNLEASHED!, Shooting Industry; February 1, 2007; Morrison, John

Self-Defense Profits!, Shooting Industry; May 1, 2004; Connor, John

The self-defense cases: How the United States Supreme Court confronted a hanging judge in the Nineteeth Century and taught some lessons for jurisprudence in the Twenty-First, American Journal of Criminal Law; July 1, 2000; Kopel, David B

SELF-DEFENSE SELLS!, Shooting Industry; June 1, 2005; Boyles, Carolee Anita

Self-defense sales: it’s all about attitude, inventory and experience., Shooting Industry; February 1, 2008; Morrison, John

Pure Fire: Self-Defense as Activism in the Civil Rights Era, The Arkansas Historical Quarterly; December 1, 2005; Riffel, Brent

Undergrad Research Shows Self-Defense May Not Be a Fixed Concept, States News Service; March 6, 2013

How to Incorporate Self-Defense Instruction into Physical Programs, Strategies: A Journal for Physical and Sport Educators; May 1, 2013; Ousley, Christopher S. Shuford, Ritchie G. Roberts, Tom

Undergrad Research Shows Self-Defense May Not Be Fixed Concept, US Fed News Service, Including US State News; March 7, 2013

The Lockean Right of Self-Defense-And Stand-Your-Ground Laws, The Washington Post; March 1, 2014; Lindgren, Jim

Patent Application Titled “Self-Defense System” under Review, Politics & Government Week; February 7, 2013

Applying Mass Media to Self-Defense Instruction in Physical Education, JOPERD–The Journal of Physical Education, Recreation & Dance; February 1, 2003; Banks, Aaron L. Reed, Julian A.

Self defense sells! Outfit your customers for personal protection!, Shooting Industry; June 1, 2005; Boyles, Carolee Anita

Self-Defense: Open and Free Legal Research of US Law

Federal Primary Materials

The U.S. federal government system consists of executive, legislative, and judicial branches, each of which creates information that can be the subject of legal research about Self-Defense. This part provides references, in relation to Self-Defense, to the legislative process, the federal judiciary, and the primary sources of federal law (cases, statutes, and regulations).

Federal primary materials about Self-Defense by content types:

Laws and Regulations

US Constitution
Federal Statutory Codes and Legislation

Federal Case Law and Court Materials

U.S. Courts of Appeals
United States courts of appeals, inclouding bankruptcy courts and bankcruptcy appellate panels:

Federal Administrative Materials and Resources

Presidential Materials

Materials that emanate from the President’s lawmaking function include executive orders for officers in departments and agencies and proclamations for announcing ceremonial or commemorative policies. Presidential materials available include:

Executive Materials

Federal Legislative History Materials

Legislative history traces the legislative process of a particular bill (about Self-Defense and other subjects) for the main purpose of determining the legislators’ intent behind the enactment of a law to explain or clarify ambiguities in the language or the perceived meaning of that law (about Self-Defense or other topics), or locating the current status of a bill and monitoring its progress.

State Administrative Materials and Resources

State regulations are rules and procedures promulgated by state agencies (which may apply to Self-Defense and other topics); they are a binding source of law. In addition to promulgating regulations, state administrative boards and agencies often have judicial or quasi-judicial authority and may issue administrative decisions affecting Self-Defense. Finding these decisions can be challenging. In many cases, researchers about Self-Defense should check state agency web sites for their regulations, decisions, forms, and other information of interest.

State rules and regulations are found in codes of regulations and administrative codes (official compilation of all rules and regulations, organized by subject matter). Search here:

State opinions of the Attorney General (official written advisory opinions on issues of state law related to Self-Defense when formerly requested by a designated government officer):

Tools and Forms

Law in Other Regions

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