Also known as: self defence · selfdefence · self-defence · self-defenses · self defenses
Written by attorneys · grounded in primary & secondary sources — see below
A privilege or affirmative defense that justifies the use of reasonable force to protect oneself or another from imminent unlawful bodily harm when the actor reasonably believes such force is necessary. The privilege is lost if the force used exceeds what is reasonably believed necessary or if the actor consented to the contact and the consent has not been withdrawn or obtained by fraud.
Select any source to read its text and confirm it supports the definition.
Spencer Silver keeps a loaded handgun in his bedroom nightstand. An intruder breaks in at night and advances toward him. Spencer draws and fires the weapon, stopping the threat. The state cannot enforce a ban that would have prevented him from having the gun ready for this use.
Sabrina Shah sees her neighbor raise a hand during an argument and honestly believes deadly force is required. She stabs the neighbor, who survives. The jury finds her belief honest but unreasonable. The charge is reduced from murder to voluntary manslaughter.
Santiago Sanchez stands his ground when an assailant advances with a knife. He could have walked away safely but chooses not to. He uses nondeadly force to repel the attack. The privilege remains available even though retreat was possible.
Samson Wells consents to a boxing match with Taylor. During the bout Taylor lands a lawful blow. Wells may not later claim self-defense against that contact. Consent removes the privilege unless obtained by fraud or withdrawn beforehand.
Stella Shapiro faces a shove from an aggressor. She responds with a single open-hand push that stops the threat. She does not draw a weapon or continue striking after the aggressor retreats. The response stays within the limit of what she reasonably believes necessary.
Serena Soto raises her fist toward an approaching attacker but stops short of contact. The attacker halts, believing a blow is imminent. Soto intended only to create apprehension and reasonably believed no greater force was needed. The act remains privileged.
At common law in some jurisdictions an honest but unreasonable belief that deadly force is necessary in self-defense mitigates murder to voluntary manslaughter. The belief must be sincere even though it fails the objective reasonableness test. Mere words or old provocations do not qualify as adequate provocation.
Under the Restatement rule self-defense remains privileged even if the actor could avoid the necessity by retreating or giving up a right. The privilege is not lost merely because retreat was feasible. The actor need not comply with a command the other has no right to enforce.
…then obtained the admission of shooting, the interrogator is advised to refer to circumstantial evidence which negates the self-defense explanation. This should enable him to secure the entire story. One text notes that "Even if he fails to do so, the inconsistency between the subject's original denial of the shooting and…
…Federalist No. 51, pp. 321-322. Madison continued: "But it is not possible to give to each department an equal power of self-defense
…Not being inured to the vicissitudes of journalistic scrutiny such an individual is more easily injured and his means of self-defense are more limited. The public is less likely to view with normal skepticism what is written about him because it is not accustomed to seeing his name in the press and expects only a…
…malice. Indeed, the want of sound memory repels the proof of malice in the same way as proof that the killing was accidental, in self-defence, or in heat of blood; and there can be no solid distinction founded upon the fact that the law presumes the existence of a sound memory. So the law infers malice from the killing when that…
…should sail for the purpose of making hostile captures, she might be dealt with as a pirate, if she made any captures except in self-defence. But this he expressly grounds upon the municipal edicts of his own country in relation to captures made by its own subjects. And he says, every declaration of war not only permits but…
An actor may not use means intended or likely to cause bodily harm beyond what the actor correctly or reasonably believes necessary for protection. Force that exceeds this limit loses the privilege. The test focuses on the harm the actor intends or should realize is likely, not on the harm that actually results.
Consent to a particular contact removes the privilege of self-defense against that contact unless the consent was obtained by fraud or later withdrawn. The actor retains the normal privilege against any contact falling outside the scope of the assent. Courts apply this rule in medical and sports settings where the scope of consent is exceeded.