The cases discussed in the portion of this work devoted to general and special pathology will certainly be useful to the medical expert, in assisting him to discover the motive of the act. To obtain the facts necessary to allow a decision of the question whether immorality or abnormality occasioned the act, a medico-legal examination is required,—an examination which is made according to the rules of science; which takes account of both the past history of the individual and the present condition,—the anthropological and clinical data.
The proof of the existence of an original, congenital anomaly of the sexual sphere is important, and points to the need of an examination in the direction of a condition of psychical degeneration. An acquired perversity, to be pathological, must be found to depend upon a neuropathic or psychopathic state.
Practically, paretic dementia and epilepsy must first come to mind. The decision concerning responsibility will depend on the demonstration of the existence of a psychopathic state in the individual convicted of a sexual crime.
This is indispensable, to avoid the danger of covering simple immorality with the cloak of disease.
Psychopathic states may lead to crimes against morality, and at the same time remove the conditions necessary to the existence of responsibility, under the following circumstances:—
1. To oppose the normal or intensified sexual desire, there may be no moral or legal notions, owing to (a) the fact that they may never have been developed (states of congenital mental weakness); or to (b) the fact that they have been lost (states of acquired mental weakness).
2. When the sexual desire is increased (states of psychical exaltation) and consciousness simultaneously clouded, the mental mechanism is too much disturbed to allow the opposing ideas, virtually present, to exert their influence.
3. When the sexual instinct is perverse (states of psychical degeneration). It may, at the same time, be intensified.
Cases of sexual delinquency that occur outside of states of mental defect, degeneration, or disease, can never be excused on the ground of irresponsibility.
In many cases, instead of an abnormal psychical condition, a neurosis (local or general) is found. Inasmuch as the transitions from a neurosis to a psychosis are easy, and elementary psychical disturbances are frequent in the former, and constant in profound perversion of the sexual life, the neurotic affection—e.g., impotence, irritable weakness, etc.—exerts an influence on the motive of the incriminating act; and a just judge, notwithstanding the lack of legal irresponsibility due to mental defect or disease, will recognize the circumstances which ameliorate the heinousness of the crime.