Here's the thing about the Tusken raiders attack on shmi: There was really no real reason why they would want to attack her. the best guess that I have is that they were hired by gradulla the hutt to attack Shmi. After all, Anakin was sold to the Hutt and he was freed after he won the pod race. Hutts do not like to give up there merchandise and well Anakin was exactly that.. valuable merchandise. Why did the farmers do nothing? - They fell under the by stander non intervention. What this means is that in a group setting, the likely hood that you would act when there is clearly trouble is slim. Also there is something called " pluralistic ignorance" this states that if you would see something on the street, say a man with a heart attack, you would not act because you do not see anyone else reacting and why should you. So the farmers are not at fault here because psychology states that this would be normal. The tusken non combatants also fit into here as well. how do we know all the tuskens are at fault?- this is common under "Obedience to authority" Basically what is happening here is that under the right conditions someone can be pushed to do anything.In other words they were forced to play along with the real threat, even though they did not really want to. are they all guilty? no not at all, but the few that committed the act influences the ones who did not want to be apart of it. The real issue is not whether anakin had the right to act as he did, but is there a reason for his actions.His mother was brutally tortured at the hands of said individuals, his promise to her that "I will come back to free you mom, I promise" (Young anakin addressing his mom " The Phantom menence") Was broken because he never got the chance to free his mother. His pain must have been felt, as you can see the change of music from right after his mom died until he realized that he broke a promise. these events in his life greatly influences his actions for the rest of the series. he will blame himself for the rest of his life. can anakin be excused from this crime? no not at all, but as Padme mentions " to be angry is to be human"( attack of the clones). Does Anakin have the right to be angry in this case: yes he does. does he have the right to take the law into his own hands? no he does not, but then again not many people go through what he went though.