A. Soundness of mind at the time of committing an offence is complementary to mental maturity as a condition for the criminal capacity of the perpetrator and is thus a condition for the criminality of his act. Accordingly, the perpetrator's mental disorder limits the criminality of his act, although not every such disorder has such radical legal consequences. If the disorder is cognitive, it must be such as to prevent the person from understanding the physical or social meaning of his conduct: if it is volitional, it must be such as to prevent him, at the time of his act, from choosing between performing the act and refraining from doing so. These are symptoms of mental disorder that negatives the criminal capacity of a person, and each of them is a necessary, but not a sufficient, condition. It is essential that this be due to a disease of the mind or an organic defect of reason. The disorder in question is therefore a radical one, and one that is also chronic if not permanent in nature, as opposed to temporary or less deep-rooted conditions such as a disturbed state, a trauma or emotional condition, impulsiveness in certain matters or urges that deviate from the normal in certain areas.
B. The following remarks are confined to the absence of criminal capacity on the volitional level, to which we shall refer in short as “volitional insanity’. This is the case where the person at the time of his act did not have a choice between acting or not acting due to a disease affecting his mind. This case is also referred to as the commission of an act as a result of an irresistible morbid impulse.