In spite of the mounting concerns about forensic psychiatric examination, there are no concrete standards of assessment with regard to criminal responsibility in Japan. Also, some cases have led to disagreements between psychiatrists and judges. To elucidate the tendency in the assessment of criminal responsibility, this study retrospectively examined seventy-one psychiatric assessments and sixty-four judgments in fifty judicial cases. The results revealed that: 1) 97.2% of psychiatrists and 100% of judges assessed the criminal responsibility of defendants based on the gnostic approach; 2) 56.3% of psychiatric assessments of criminal responsibility were consistent with the court's decision; 3) in comparison with judges, psychiatrists did not significantly examine situational factors when they assessed their cases; and 4) their descriptions of the assessment were variable and not standardized. These results show that we psychiatrists should consider at least fourteen factors: motive/cause, modus operandi, hesitation, surrendering, escape, knowledge of crime, their statements, their specific behaviors/emotions (before, during and after the fact), and memory, as considerable items. To standardize the classification and description of the psychiatric assessment of criminal responsibility, the German five-grade assessment (responsible, diminished responsibility cannot be excluded, diminished responsibility, non-responsibility cannot be excluded, and non-responsibility) is applicable to the Japanese criminal justice system.