From Nancy Grace's show (i know, I know. lol)
Richard Novia (the head of security until 2008 at Newton High School): Aspergers was part of it and there were other mental disorders that he (the killer) dealt with. I interacted with that boy for several years. I can testify to this.
I wonder why the head of security was interacting with the killer when he was a student.
I think they were concerned for his safety so a security officer may have been assigned to keep him secure.
http://online.wsj.com/article/SB10001424127887324677204578183910797348422.html
Their fear wasn't that he was dangerous. "It was completely the opposite," said Richard J. Novia, the director of security at Newtown School District at the time in 2007. "At that point in his life, he posed no threat to anyone else. We were worried about him being the victim or that he could hurt himself."
ETA;
snip
The scrawny teenager with a mop of brown hair evoked feelings of sympathy, not fear, from teachers and the few classmates who even noticed him.
HTH