Dugdale's original examination covered 709 cases out of about 1200 that were supposed to be living at the time. Of this number, 180 are put down as having received institutional and outdoor relief. The criminals and offenders are put down at 140. Habitual thieves convicted and unconvicted are listed at 60. Common prostitutes are put down at 50.
After Dugdale's investigation the family, from industrial and other conditions, became scattered and spread out over many states. A record has lately been made of the descendants of this family, the later record showing much improvement in the stock. This must be due to environment. It seems fairly certain that with time and opportunity, it will not much longer be a marked family.
Quite aside from the history, it seems certain that no results such as shown by Dugdale could have followed from inheritance. Defectiveness is a recessive factor; normality a dominant one. If such were not true, this would be a world of feeble-minded. If the Mendelian law held good in this regard, from a union of a defective and a normal person, three out of four would be normal, but as a matter of fact, the percentage of normal is no doubt much greater. It is only when both father and mother are feeble-minded that feeble-mindedness is sure to show in the offspring. With the modern care of this sort of defectives, the chance of breeding is growing rapidly less.
The Kallikak family is cited as another illustration showing the possible inheritance of criminality and poverty through a defective strain. This family, so far as shown, makes it still clearer that what some authors have charged to heredity is simply due to environment. These investigations do not show the need of controlling birth but do prove the necessity of improving environment. It is not possible to speak with certainty as to heredity and environment. The thorough investigation of these two factors which make up life is still in its infancy, but scientists are working out the problem, and we may be confident that with the right attitude toward crime, a remedy will be found for such cases as result from environment.
The criminologist has always looked for the cause of crime in some other direction than in the inherent wickedness of the criminal. Only those who make and enforce the law believe that men commit crimes because they choose the wrong.