In general, people with ADHD do not conform to society's expectations of how a human brain should work. That means they're more likely to be marginalized & targeted, and likely have fewer resources at their disposal if they are at risk; so they are both more likely to become a homicide target and have less protection if they do. They're also more likely to engage in risk taking behaviour, much of which could increase one's risk of being a victim of a homicide.