Recipe for a Theory of Self-Defense: The Ingredients, and Some Cooking Suggestions


Larry Alexander

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Self-defense and its close relative, defense of others, are uses of force against another person — Attacker — for the purpose of preventing Attacker from harming another’s person or property. These uses of force are called self-defense (SD) when employed by the one whose person or property is threatened (the Victim, or V); they are called defense of others (DO) when employed by a non-threatened third party who is not in V’s family (TP).

SD and DO are preemptive uses of force because they occur before the acts they are intended to prevent occur. They thus belong to the family of preemptive measures that harm people or restrict their liberty in order to prevent them from harming others in the future. Examples of preemptive measures other than SD and DO include preventive detention, restraining orders, gun control laws, and similar laws making possession of certain items illegal for fear of their misuse.

Because SD and DO are preemptive, they operate in the realm of epistemic uncertainty. V and TP can never be certain the feared acts will occur. They can never be certain that if the acts occur, what their consequences will be. They can never be certain what alternative to SD and DO for averting the feared harms exist. And they can never be certain what the status of the presumed Attacker is — that is, whether the presumed Attacker is culpable or nonculpable. I will have had a lot more to say about these epistemic points in due course.