Is AS an excuse for bad behavior?
(In response to the title question, posted as a topic on Wrong Planet.)
AS is not an excuse for bad behavior, but when someone has AS, the definition of "bad behavior" changes. It must take into account the amount of control a person has over his actions.
Think of the difference between these scenarios.
1. Mark is in class. He is tired and overloaded because it's hot and he is wearing a shirt that's made of polyester. A child behind him is fidgeting, tapping two pencils against his desk in a drumbeat, until he grows bored and begins tapping the pencils against Mark's back. This is the last straw for Mark, and he stands up, throws his own pencil at his classmate, and yells, "Stop it!" repetitively, finally collapsing in tears and having to be removed from the classroom by his aide.
2. Mark is older now, and he's in high school. Through therapy, he has been taught how to recognize the signs of overload and how to manage stress. He has permission to leave the classroom if he needs to in order to calm himself. However, Mark has decided that he shouldn't have to bother with all of that, and this morning he put on a polyester shirt even though he knows it's going to bug him all day, especially since it's a long-sleeved shirt and the classroom will be a little too warm. When his bored classmate starts tapping on the desk, Mark can feel that his stress level is rising and he's starting to have trouble understanding the teacher's chemistry lecture, but he doesn't use his hall pass to leave the situation and calm down. Instead, he stays in the classroom until, when his classmate starts tapping on his back, he explodes, throws his pencil, and has to be removed from the room.
3. It's an average day for Mark, and he's feeling fine. This morning he put on comfortable clothing, and the classroom is pleasantly cool. Mark is enjoying an interesting lecture about the periodic table when his classmate grows bored and starts tapping his pencil. Mark doesn't like his classmate; the other boy doesn't share Mark's love of learning and looks down on Mark for being "a nerd", and Mark gets some satisfaction from his knowledge that his grades in chemistry are a lot better than his classmate's. As time goes on, Mark gets angrier at his classmate, and when his classmate starts tapping the pencil against Mark's back, Mark forgets his social skills, turns around, throws his pencil at his classmate, and yells, "Hey! Just because you're an idiot who doesn't want to learn, doesn't mean the rest of us don't want to listen!" This time, Mark isn't out of control, so a stern word from the teacher causes him and his classmate to sit down and go back to the lecture, though the feud between him and his classmate has just intensified.
In the first situation, the child had little control over what happened to him and didn't have much knowledge of what was going on, what might happen and how to prevent it. Therefore he wasn't responsible for what happened; the class disruption wasn't his fault. In the second situation, the teenager knowingly did not deal with his AS traits, and it caused a disturbance. He is responsible for being negligent in dealing with his sensory overload, in a similar way to how a person might be responsible for having an asthma attack if they knowingly exposed themselves to an allergen without using medication.
The third scenario is an example of someone with AS making a voluntary choice that ends in the disruption of the chemistry lesson, and in terms of discipline, Mark deserves his teacher's reprimand just as much as his pencil-tapping classmate does. If he had been NT, he might have given his classmate a dirty look and communicated that way, but since he has AS, it was easier for him to forget himself and shout instead. However, in this case Mark was not overwhelmed and was able to consider his actions; he could have chosen to use his permission to leave the room, turned around and asked his classmate to stop tapping the pencil, or asked the teacher for help.
One caveat, though: In all three scenarios, Mark's classmate also deserves some of the blame. It's not much blame, since Mark wasn't being hurt and the classmate was unaware of how annoyed he might become. However, disturbing a classmate who is trying to listen to a lesson is not polite, and just because it's the Aspie who has the louder reaction, doesn't mean that the classmate doesn't also deserve a reprimand.