So a criminal can't claim self-defense. Is there also a law that authorizes excessive force by the vigilantes? Or can he seek civil damages for the beating?

I don't see how anyone would reasonably think that that the use of force is immediately necessary to protect from a thief that is running away.

@Barmar Right, both sides could be criminally liable. In the above case, the thief could be charged with the Texas crime of deadly conduct and the original robbery, the members of the crowd with assault. The thief could not sue for damages, see edits.

@JoeW Read the very clear title of the question. The thief potentially gains the right of self defense because he is being beaten by the crowd. In some states the thief does, in other states they do not because he was committing a crime.

And why exactly would a crowd of bystanders have any need at all to use force to stop a thief? You seem to be missing my point that someone stealing something doesn't mean that they need to be stopped by force or that people should put themselves in a situation where serious harm or death could occur.

@JoeW You are completely ignoring the premise of the question. Try reading it again.

I have read it multiple times and I still don't see any place where the use of force would be justified for simple theft let alone force that would rise to the level that someone would consider the need to defend themselves from it. The simple fact remains is that when considering justification for use of force against someone there has to be an actual threat to the person and a simple purse snatcher running away isn't much of a threat to anyone.

@JoeW You're purposely being obstinate. If you're walking down the street and a mob beats you for no reason, you're entitled to use force via self defense. The people in the mob committed a crime but you didn't. If you're running from a crime and a mob beats you because they saw you commit a crime, the right to self defense is removed in Texas. If you do use force, both you and people in the mob have committed crimes.

I would ask you the same, the example you use isn't just a simple crime rather it is people using violence and force against you which is the very example of justified self defense. The question however was using theft as an example crime and there is no way to justify a mob chasing and attacking a person over simple theft and instead it becomes a simple example of what you said where the thief is now justified in their self defense.

@JoeW The gist of this answer is that your last sentence is wrong for Texas. The thief was engaged in criminal activity and therefore is not justified in self defence according to the paragraph quoted. It does not matter whether the mob was justified in beating the thief, or if that also constitutes a crime. The fact that the thief was committing a crime immediately waives his right to self defence completely, regardless of any other external factors, including whether the thing he’s defending himself against is justified or not.

@JanusBahsJacquet I'm not seeing that from my reading of the link, the pertinent part is not quoted in the answer. The lack of recovery of damages only takes place if the damage occurred in the prevention of the crime or the apprehension of the suspect. Someone lying on the ground with an injury is not being apprehended during a beat down. Without that exclusion I cannot be sued if I beat up someone on their release from custody because they did something to me years before.

@JanusBahsJacquet What I am reading from the provided information is that if they " reasonably believes the force is immediately necessary to protect" and the act of stealing alone and attempting to flee does not mean that anyone is in danger and needs protecting. It does not say that committing a crime is justification to use force.

@David I wasn’t talking about recovering of damages (the second part of the answer), only about whether the thief’s use of force could be justified as self defence.

@JoeW You are still arguing about the mob’s use of force. That’s irrelevant here. The question and answer are about the thief’s use of force. Obviously, a mob chasing someone cannot reasonably believe that kicking and beating that person while he’s lying on the ground is immediately necessary to protect themselves from him. No one is disputing that. But this is about the thief shooting a member of the mob. In Texas, the fact that the thief was committing a crime at the time the shot was fired means he has no right to self defence, and therefore no right to shoot.

@JanusBahsJacquet No, I am still arguing that theft alone doesn't put anyone in any sort of danger and will never justify the use of force. There is a reason that most stores have a policy of not confronting shoplifters because it isn't a crime that puts employees in danger. The situation you are talking about only comes after the thief is chased down and is assaulted while injured and on the ground and is themselves a victim of a crime. Someone stealing a purse doesn't give a mob of people the right to assault them after they flee.

@JoeW No one is saying it does. Theft alone obviously does not justify the use of force. But that’s not relevant, because it’s not what the question is about. The situation I am talking about is the situation the question is about. What you’re talking about is a separate part of the scenario, a part of the stage that forms the background of the question, but not what the question is about. If you want to argue about how far a group of vigilantes can reasonably go when apprehending a suspect, you should ask a separate question about it, because it’s not what this one is about.

@JanusBahsJacquet the issue remains that committing a crime isn’t blanket justification to lose the right to self defense.

@JoeW I agree that it shouldn’t be, but the text seems pretty unequivocal that in Texas, it is. It’s a requirement that “the actor reasonably believes the force is immediately necessary”, and this belief can only be considered reasonable if the actor is not engaging in criminal activity.

@JanusBahsJacquet As I have stated multiple times theft of an item is not reasonable belief for a bystander to use force as not all criminal activity results in the need to use force to stop it.

@JoeW The point is that it doesn't matter if the mob's use of force is justified. The mob can be prosecuted for beating the thief (because the beating wasn't necessary), and the thief can be prosecuted for trying to defend himself (because self-defense is precluded).

It's not making vigilante justice legal, just taking away a right from the original criminal.

@JoeW And as you have been told multiple times, that is irrelevant. The text does not distinguish violent crimes from non-violent ones, only Class C traffic misdemeanours are exempt. Forget about the mob, it’s not important. By the paragraph quoted from Texas legislation, if a random stranger attacks you while you’re doing something illegal (e.g., transferring company funds to your own account or hacking into a security system), you cannot legally defend yourself in Texas. The attacker commits a crime by attacking you; you commit a crime by defending yourself. Both are crimes.

@JanusBahsJacquet Again, it isn't irrelevant to point out that the crime in question will impact the justification of the use of force. The question was asking about theft and a fleeing suspect which is clearly not a case in which the use of force would be justified and it seems clear that it wouldn't be justified in most cases of theft unless there are other crimes involved such as assault, battery, robbery or other things. The words that you keep trying to point to clearly spell out reasonable belief which is not present in the case of a theft and fleeing the scene.

@JanusBahsJacquet The law isn't saying that you have the right to assault someone just because you think that they have committed a crime.

@JoeW And nobody ever claimed that it did. I very clearly said, “The attacker commits a crime by attacking you”. Similarly, the mob that chases the thief commits a crime by beating him up. That is not being questioned. You keep completely ignoring the actual question being asked and focussing only on force being used against the criminal. So let me repeat for the tenth time, in big bold letters so perhaps you’ll understand it:

THE MOB IS NOT JUSTIFIED IN USING FORCE AGAINST THE THIEF. THE MOB IS COMMITTING A CRIME. THE MOB HAS NO JUSTIFICATION. BEATING THE THIEF IS NOT LEGAL.

That is established without any doubt, but in Texas, it is irrelevant to whether the thief is justified in using force against the mob.