Sec. 9.02. JUSTIFICATION AS A DEFENSE. It is a defense to prosecution that the conduct in question is justified under this chapter.(please note that Ch9 doesn't keep you from being prosecuted only that it is a defense if you ARE prosecuted. You still have to convince a jury. - C)
Sec. 9.05. RECKLESS INJURY OF INNOCENT THIRD PERSON. Even though an actor is justified under this chapter in threatening or using force or deadly force against another, if in doing so he also recklessly injures or kills an innocent third person, the justification afforded by this chapter is unavailable in a prosecution for the reckless injury or killing of the innocent third person. (you don't have carte blanch even in Texas - C)
Sec. 9.06. CIVIL REMEDIES UNAFFECTED. The fact that conduct is justified under this chapter does not abolish or impair any remedy for the conduct that is available in a civil suit.(just because the DA doesn't come after you doesn't mean some ambulance chaser cannot - C)
SUBCHAPTER C. PROTECTION OF PERSONS
Sec. 9.31. SELF-DEFENSE. (a) Except as provided in Subsection (b), a person is justified in using force against another when and to the degree the actor reasonably believes the force is immediately necessary to protect the actor against the other's use or attempted use of unlawful force. The actor's belief that the force was immediately necessary as described by this subsection is presumed to be reasonable if the actor:
(1) knew or had reason to believe that the person against whom the force was used:
(A) unlawfully and with force entered, or was attempting to enter unlawfully and with force, the actor's occupied habitation, vehicle, or place of business or employment;
(B) unlawfully and with force removed, or was attempting to remove unlawfully and with force, the actor from the actor's habitation, vehicle, or place of business or employment; or
(C) was committing or attempting to commit aggravated kidnapping, murder, sexual assault, aggravated sexual assault, robbery, or aggravated robbery;
(2) did not provoke the person against whom the force was used; and
(3) was not otherwise engaged in criminal activity, other than a Class C misdemeanor that is a violation of a law or ordinance regulating traffic at the time the force was used.
(b) The use of force against another is not justified:
(1) in response to verbal provocation alone;
(2) to resist an arrest or search that the actor knows is being made by a peace officer, or by a person acting in a peace officer's presence and at his direction, even though the arrest or search is unlawful, unless the resistance is justified under Subsection (c);
(3) if the actor consented to the exact force used or attempted by the other;
(4) if the actor provoked the other's use or attempted use of unlawful force, unless:
(A) the actor abandons the encounter, or clearly communicates to the other his intent to do so reasonably believing he cannot safely abandon the encounter; and
(B) the other nevertheless continues or attempts to use unlawful force against the actor; or
(5) if the actor sought an explanation from or discussion with the other person concerning the actor's differences with the other person while the actor was:
(A) carrying a weapon in violation of Section 46.02; or
(B) possessing or transporting a weapon in violation of Section 46.05.
Sec. 9.32. DEADLY FORCE IN DEFENSE OF PERSON. (a) A person is justified in using deadly force against another:
(1) if the actor would be justified in using force against the other under Section 9.31; and
(2) when and to the degree the actor reasonably believes the deadly force is immediately necessary:
(A) to protect the actor against the other's use or attempted use of unlawful deadly force; or
(B) to prevent the other's imminent commission of aggravated kidnapping, murder, sexual assault, aggravated sexual assault, robbery, or aggravated robbery.
Sec. 9.33. DEFENSE OF THIRD PERSON. A person is justified in using force or deadly force against another to protect a third person if:
(1) under the circumstances as the actor reasonably believes them to be, the actor would be justified under Section 9.31 or 9.32 in using force or deadly force to protect himself against the unlawful force or unlawful deadly force he reasonably believes to be threatening the third person he seeks to protect; and
(2) the actor reasonably believes that his intervention is immediately necessary to protect the third person.
SUBCHAPTER D. PROTECTION OF PROPERTY
Sec. 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.
Sec. 9.42. DEADLY FORCE TO PROTECT PROPERTY. A 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.
Sec. 9.43. PROTECTION OF THIRD PERSON'S PROPERTY. A person is justified in using force or deadly force against another to protect land or tangible, movable property of a third person if, under the circumstances as he reasonably believes them to be, the actor would be justified under Section 9.41 or 9.42 in using force or deadly force to protect his own land or property and:
(1) the actor reasonably believes the unlawful interference constitutes attempted or consummated theft of or criminal mischief to the tangible, movable property; or
(2) the actor reasonably believes that:
(A) the third person has requested his protection of the land or property;
(B) he has a legal duty to protect the third person's land or property;.(this is why I can guard someone's property - C)
or
(C) the third person whose land or property he uses force or deadly force to protect is the actor's spouse, parent, or child, resides with the actor, or is under the actor's care.