There had been argument concerning the difference between the agnostic approach and the gnostic approach to the psychiatric perspective of criminal responsibility until the landmark ruling by the 3rd court of the Japanese Supreme Court in 1984. The decision upheld the gnostic approach and affirmed that the defendant's criminal responsibility should be based on such factors as psychopathology, motive, modus operandi, situation surrounding the crime, and pre-morbid personality, as long as the offense was not directly motivated by the delusion or hallucination. The gnostic explanation includes so many various factors that the psychiatric testimony cannot easily be objective, while agnostic experts can find a conclusion about criminal responsibility only by psychiatric diagnosis. To establish a standard, the authors summarized the means of determination of criminal responsibility. The authors also discussed various topics related to criminal responsibility including Asperger's syndrome, illicit drug intoxication, and prescribed drug intoxication.