After having been in charge of a psychiatric evaluation in a death penalty case, the authors conducted an investigation of verdicts in past cases where the death penalty was sought by the prosecution and where criminal responsibility became the focus. The study examined the details of 11 cases from between January 1, 1980, and February 28, 2019, in which there were 3 or more victims (deceased) outside of the family, and in which the verdict recognized such psychotic symptoms as hallucinations and delusions as having related to the criminal act. The results showed that while in past cases, where diminished responsibility was recognized the accused would avoid the death penalty and be sentenced to life imprisonment, more recently it has become less likely for courts to recognize diminished responsibility or insanity, or to allow a reduction in punishment in light of extenuating circumstances. Thus, the death penalty has continually been awarded on the grounds of full criminal responsibility. Previously, judgments of diminished responsibility were handed down in cases where delusions deriving from mental disorders played a part in the motivation for the crime and then doubts remained about the accused's ability to understand the situation they were in and to control their behavior. More recently, death penalties have been awarded in consideration of the separation between "motivation" and "the criminal act itself," so that although in cases where a mental disorder did influence the motivation, the criminal act itself is seen as one of normal psychology, and so on. Moreover, while in the past emphasis was placed on diagnosis following the criminal act, with diagnoses of schizophrenia having a significant effect and the influence of agnosticism presumed to remain, more recently there has been a growing tendency for gnosticism, in which the influences and mechanisms of mental disorders and normal psychology on the criminal act are analyzed in detail, and the defendant's capacities and lack of mental illness are more likely to be highlighted. The contributing factors are thought to be the shift to gnosticism (1984-) and the spread of the seven focal points (2006-), the introduction of the victim participating system (2008) and lay judge trials (2009), the trend toward severe punishment, and the normalization of people with mental disorders. When the social impact of the crime is significant-for example, when there are many victims and they are not family members-it is less likely for diminished responsibility or insanity to be recognized and the death penalty will follow. Finally, beyond the diagnosis, we suggest visually illustrating the influence of illness and other factors on the criminal act in a way that is easy to understand through case formulation and making a life chart to increase the scientificness and transparency of a psychiatric evaluation.
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