When I was in high school, I used to steal money from my mother's wallet. (We didn't have credit cards or computers back then.) I honestly don't know why I would do it. I would take out a twenty dollar bill and use it to buy things like record albums (this was the 60's.)
I grew into a very honest adult but it took some time.
When I was a young adult (I secretly left home twice, once when I was 21, and again when I was 24, with my mother not knowing for years where I was.) I committed a lot of petty theft, using bad credit cards and passing bad checks, to buy groceries, gasoline, and the like. It's how I "got by."
I got caught a couple of times and had to "make good."
I could have gone back home and lived off of my mother at any time, but this was the way I saw to make it on my own.
I grew up into a very honest adult. But, I'm sure that my inability to connect with others fruitfully at the time was a large part of what I was doing.
If I had been caught by my mother, stealing from her wallet, I most certainly would have lied to her. I would have done so out of fear. I was an only child, and, if I had asked my mother for money, I'm certain that she would have given it to me.
To the best of my knowledge, neither of my autistic sons has ever stolen anything. The lower funcioning is non-verbal and probably wouldn't understand the concept. The higher functioning 18 year old would not know the difference between stealing something and taking something inadvertantly. He does not understand the role of motive in doing something wrong.
I know this offers little help, but I hope it offers some insight into the mind of an aspie adolescent, as I recall forty years later.