CRIMINAL PSYCHOLOGY.
INTRODUCTION.
OF all disciplines necessary to the criminal justice in addition to the knowledge of law, the most important are those derived from psychology. For such sciences teach him to know the type of man it is his business to deal with. Now psychological sciences appear in various forms. There is a native psychology, a keenness of vision given in the march of experience, to a few fortunate persons, who see rightly without having learned the laws which determine the course of events, or without being even conscious of them. Of this native psychological power many men show traces, but very few indeed are possessed of as much as criminalists intrinsically require.
In the colleges and pre-professional schools we jurists may acquire a little scientific psychology as a “philosophical propaedeutic,” but we all know how insufficient it is and how little of it endures in the business of life. And we had rather not reckon up the number of criminalists who, seeing this insufficiency, pursue serious psychological investigations.
One especial psychological discipline which was apparently created for our sake is the psychology of law, the development of which, in Germany, Volkmar[1] recounts. This science afterward developed, through the instrumentality of Metzger[2] and Plainer,[3] as criminal psychology. From the medical point of view especially, Choulant’s collection of the latter’s, “Quaestiones,” is still valuable. Criminal psychology was developed further by Hoffbauer,[4] Grohmann,[5] Heinroth,[6] Schaumann,[7] Münch,[8] Eckartshausen,[9] and others. In Kant’s time the subject was a bone of contention between faculties, Kant representing in the quarrel the philosophic, Metzger, Hoffbauer, and Fries,[10] the medical faculties. Later legal psychology was simply absorbed by psychiatry, and thereby completely subsumed among the medical disciplines, in spite of the fact that Regnault,[11] still later, attempted to recover it for philosophy, as is pointed out in Friedreich’s[12] well-known text-book (cf. moreover V. Wilbrand’s[13] text-book). Nowadays, criminal psychology, as represented by Kraus,[14] Krafft-Ebing,[15] Maudsley,[16] Holtzendorff,[17] Lombroso,[18] and others has become a branch of criminal anthropology. It is valued as the doctrine of motives in crime, or, according to Liszt, as the investigation of the psychophysical condition of the criminal. It is thus only a part of the subject indicated by its name.[19] How utterly criminal psychology has become incorporated in criminal anthropology is demonstrated by the works of Näcke,[20] Kurella,[21] Bleuler,[22] Dallemagne,[23] Marro,[24] Ellis,[25] Baer,[26] Koch,[27] Maschka,[28] Thomson,[29] Ferri,[30] Bonfigli,[31] Corre,[32] etc.
Literally, criminal psychology should be that form of psychology used in dealing with crime; not merely, the psychopathology of criminals, the natural history of the criminal mind. But taken even literally, this is not all the psychology required by the criminalist. No doubt crime is an objective thing. Cain would actually have slaughtered Abel even if at the time Adam and Eve were already dead. But for us each crime exists only as we perceive it,—as we learn to know it through all those media established for us in criminal procedure. But these media are based upon sense-perception, upon the perception of the judge and his assistants, i.e.: upon witnesses, accused, and experts. Such perceptions must be psychologically validated. The knowledge of the principles of this validation demands again a special department of general psychology—even such a pragmatic applied psychology as will deal with all states of mind that might possibly be involved in the determination and judgment of crime. It is the aim of this book to present such a psychology. “If we were gods,” writes Plato in the Symposium, “there would be no philosophy”—and if our senses were truer and our sense keener, we should need no psychology. As it is we must strive hard to determine certainly how we see and think; we must understand these processes according to valid laws organized into a system—otherwise we remain the shuttlecocks of sense, misunderstanding and accident. We must know how all of us,—we ourselves, witnesses, experts, and accused, observe and perceive; we must know how they think,—and how they demonstrate; we must take into account how variously mankind infer and perceive, what mistakes and illusions may ensue; how people recall and bear in mind; how everything varies with age, sex, nature, and cultivation. We must also see clearly what series of influences can prevail to change all those things which would have been different under normal conditions. Indeed, the largest place in this book will be given to the witness and the judge himself, since we want in fact, from the first to keep in mind the creation of material for our instruction; but the psychology of the criminal must also receive consideration where-ever the issue is not concerned with his so-called psychoses, but with the validation of evidence.
Our method will be that fundamental to all psychological investigation, and may be divided into three parts:[33]
1. The preparation of a review of psychological phenomena.
2. Study of causal relationships.