Attention Deficit Hyperactivity Disorder (ADHD) is a neurobehavioral disorder which is characterized by inattention, hyperactivity, and impulsivity (Green, Chess, Conquest & Yegla, 2011). The symptom of impulsivity is thought to play a role in the relationship between childhood ADHD and adult criminality (Savolainen, Hurtig, & Ebeling, 2010). Because of the generally high prevalence of learning disorders among inmates it has been difficult to distinguish whether the relationship is causal or correlational. During the 1990s there was an explosion of childhood diagnoses of ADHD (Gordon & Moore, 2005). Interestingly, as this cohort began adolescence, in the early 2000s, the American criminal justice system began to see an increase of inmates with ADHD (Gordon & Moore, 2005). This suggests there is more than a correlational relationship. This paper will analyze the link between childhood ADHD and adult criminality.