Between 30% to 65% of individuals with command hallucinations to harm others (referred to below as “harm-other” command hallucinations) comply with those hallucinations. Clinicians should be familiar with four factors associated with persons acting on harm-other command hallucinations when conducting a violence risk assessment. First, persons are more likely to act on auditory hallucinations to harm others when they perceive the voice as powerful. Clinicians should ask their patient if they experience associated feelings of helplessness or powerlessness associated with the voice and if they believe there would be a bad outcome if the voice command is not followed. Second, individuals who believe that following the directive of the command hallucination will benefit them or more likely to comply with the harm-other command hallucination. Third, persons are more like to follow harmful command hallucinations when they are associated with a congruent delusion. As an example, a man who hears a voice to kill his neighbor is more likely to act on this command if he believes his neighbor has been invaded by an evil alien who is plotting to kill him. Fourth, patients with schizophrenia who experience command hallucinations that generate negative emotions–such as anger, anxiety or sadness–are more likely to act violently than those individuals with voices that generate positive emotions.
Scott CL and Resnick PJ: Clinical assessment of aggression and violence. In Principles and Practice of Forensic Psychiatry, Third Edition (Editors: Rosner R and Scott CL); CRC Press, Taylor & Francis Group, New York, 2017, pp 623-632.