[Jeff22]

Self Defense in the Law of Illinois:

(720 ILCS 5/Art. 7 heading)
ARTICLE 7. JUSTIFIABLE USE OF FORCE; EXONERATION

(720 ILCS 5/7‑1) (from Ch. 38, par. 7‑1)
Sec. 7‑1. Use of force in defense of person.

(a) A person is justified in the use of force against another when and to the extent that he reasonably believes that such conduct is necessary to defend himself or another against such other's imminent use of unlawful force. However, he is justified in the use of force which is intended or likely to cause death or great bodily harm only if he reasonably believes that such force is necessary to prevent imminent death or great bodily harm to himself or another, or the commission of a forcible felony.

(720 ILCS 5/7‑2) (from Ch. 38, par. 7‑2)
Sec. 7‑2. Use of force in defense of dwelling.
(a) A person is justified in the use of force against another when and to the extent that he reasonably believes that such conduct is necessary to prevent or terminate such other's unlawful entry into or attack upon a dwelling. However, he is justified in the use of force which is intended or likely to cause death or great bodily harm only if:
(1) The entry is made or attempted in a violent,
riotous, or tumultuous manner, and he reasonably believes that such force is necessary to prevent an assault upon, or offer of personal violence to, him or another then in the dwelling, or
(2) He reasonably believes that such force is
necessary to prevent the commission of a felony in the dwelling.

(720 ILCS 5/7‑13) (from Ch. 38, par. 7‑13)
Sec. 7‑13. Necessity.
Conduct which would otherwise be an offense is justifiable by reason of necessity if the accused was without blame in occasioning or developing the situation and reasonably believed such conduct was necessary to avoid a public or private injury greater than the injury which might reasonably result from his own conduct.
(Source: Laws 1961, p. 1983.)

(720 ILCS 5/7‑14) (from Ch. 38, par. 7‑14)
Sec. 7‑14. Affirmative defense. A defense of justifiable use of force, or of exoneration, based on the provisions of this Article is an affirmative defense.
(Source: Laws 1961, p. 1983.)
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Wisconsin State Statute 939.48 -- Self Defense and the Defense of Others:

(1.) A person is privileged to threaten or intentionally use force against another for the purpose of preventing or terminating what the person reasonably believes to be an unlawful interference with his or her person by such other person. The actor may intentionally use only such force or threat thereof as the actor reasonably believes is necessary to prevent or terminate the (unlawful) interference. The actor may not intentionally use force which is intended or likely to cause death or great bodily harm unless the actor reasonably believes that such force is necessary to prevent imminent death or great bodily harm to himself or to herself.
(2.) Provocation affects the privilege of self-defense as follows: (a.) A person who engages in unlawful conduct of a type likely to provoke others to attack him or her and thereby does provoke an attack is not entitled to claim the privilege of self defense against such attack, except when the attack, which ensues, is of a type causing the person engaging in the unlawful conduct to reasonably believe that he or she is in imminent danger
of death or great bodily harm. In such a case, the person engaging in the unlawful conduct is privileged to act in self-defense, but the person is not privileged to resort to the use of force intended or likely to cause death to the person's assailant, unless the person reasonably believes that he or she has exhausted every other reasonable means to escape from or otherwise
avoid death or great bodily harm at the hands of his or her assailants. (b.) The privilege lost by provocation may be regained if the actor in good faith withdraws from the fight and gives adequate notice thereof to his or her assailant. (c.) A person who provokes an attack, whether by lawful or unlawful conduct, with intent to use such an attack as an excuse to cause death or great bodily harm to his or her assailant is not entitled to claim the privilege of self-defense.
(4.) A person is privileged to defend a third person from real or apparent unlawful interference by another under the same conditions and by the same means as those under and by which the person in privileged to defend himself or herself from real or apparent unlawful interference, provided that the person reasonably believes that the facts are such that the third person would be privileged to act in self-defense and that the person's intervention is necessary for the protection of the third person.

Wisconsin State Statute 939.45 -- Privilege: The fact that the actor's conduct is privileged, although otherwise criminal, is a defense to prosecution for any crime based on that conduct.The defense of privilege can be claimed under any of the following circumstances:
(2.) When the actor's conduct is in defense of persons or property under any of the circumstances described in 939.48 (Self-Defense and the Defense of others) or 939.49 ((Defense of Property and protection against retail theft):
(3.) When the actor's conduct is in good faith and is an apparently authorized and reasonable fulfillment of any duties of a public office; or
(4.) When the actor's conduct is a reasonable accomplishment of a lawful arrest.
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These are just a couple of examples of how the "self defense" issue is addressed in statutes. Most states probably have similar language. I find it interesting that Virginia does not address "self defense" in statutory law, but rather depends on case law to determine precedent. That has to make being involved in any use of force in self defense incident quite an adventure . . .