SUBCHAPTER B. JUSTIFICATION GENERALLY
§ 9.21. Public Duty
(a) Except as qualified by Subsections (b) and (c), conduct is justified if the actor reasonably believes the conduct is required or authorized by law, by the judgment or order of a competent court or other governmental tribunal, or in the execution of legal process.
(b) The other sections of this chapter control when force is used against a person to protect persons (Subchapter C),
to protect property (Subchapter D), for law enforcement (Subchapter E), or by virtue of a special relationship (Subchapter F).
(c) The use of deadly force is not justified under this section unless the actor reasonably believes the deadly force is specifically required by statute or unless it occurs in the lawful conduct of war. If deadly force is so justified, there is no duty to retreat before using it.
HERE"S WERE IT GETS REALLY GOOD:
9.41. Protection of One's Own Property
(a) A person in lawful possession of land or tangible, movable property is justified in using force against another when and to the degree the actor reasonably believes the force is immediately necessary to prevent or terminate the other's trespass on the land or unlawful interference with the property.
(b) A person unlawfully dispossessed of land or tangible, movable property by another is justified in using force against the other when and to the degree the actor reasonably believes the force is immediately necessary to reenter the land or recover the property if the actor uses the force immediately or in fresh pursuit after the dispossession and:
(1) the actor reasonably believes the other had no claim of right when he dispossessed the actor; or
(2) the other accomplished the dispossession by using force, threat, or fraud against the actor.
Acts 1973, 63rd Leg., p. 883, ch. 399, § 1, eff. Jan. 1, 1974. Amended by Acts 1993, 73rd Leg., ch. 900, § 1.01, eff. Sept. 1, 1994.
§ 9.42.
Deadly Force to Protect PropertyA person is justified in using deadly force against another to protect land or tangible, movable property:
(1) if he would be justified in using force against the other under Section 9.41; and
(2) when and to the degree he reasonably believes the deadly force is immediately necessary:
(A) to prevent the other's imminent commission of arson,
burglary, robbery, aggravated robbery, theft during the nighttime, or criminal mischief during the nighttime; or
(B)
to prevent the other who is fleeing immediately after committing burglary, robbery, aggravated robbery, or theft during the nighttime from escaping with the property; and
(3) he reasonably believes that:
(A) the land or property cannot be protected or recovered by any other means; or
(B) the use of force other than deadly force to protect or recover the land or property would expose the actor or another to a substantial risk of death or serious bodily injury
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