Children with diagnosed psychopathologies may experience aggravation of those illnesses with their exposure to media violence. Children with the most common, often undiagnosed, form of psychopathology—Disruptive Behavior Disorders (DBDs)—manifested changes in heart rate, heart vagal heart tone and other psychophysiological reactions to media violence. Children without a diagnosis did not manifest these same psychophysiological responses. These reactions, or the absence of them, made determining the effect of violent media on children a more reliable measure than acted out behavior, which can be more susceptible to experimenter interpretation and, thus, experimenter bias. This paper explains why there is a difference in the psychophysiological responses between the two groups. Future research should more carefully examine the putative psychological harm violent television content may impose on children with psychological ailments.