>> let me start by being very clear. there's no link between mental illness and violence and there's certainly no link between an autistic spectrum disorder and violence. to be clear, we don't talk about autism anymore. we talk aboutous testic sp -- a spectrum disorders. people with autistic disorders may be very focused on interests, often they're focused on trains or subways. he could certainly be focused on guns. that may explain the interest. but there's no link between the mental illness and violence. >> there's a lot being made about the relationship the mother and the son had, not just their relationship but common interests and their bonding over guns. i actually want to read to you something that the ap -- they spoke to a psychologist, peter langman. he said in some cases parents