Scientists for years have been trying to find what causes a human being to commit a crime. There have been studies done on the biological causes of criminality, the psychological causes of criminality, if mental disorders cause crime, the sociological causes and theories of crime causation and the theories of subculture causing crimes.
The biological studies consisted of studies involving twins, both identical and fraternal, incarcerated individuals within a penal institution and children. In 1920 German physician, Johannes Lange, found 30 pairs of twins- 13 identical and 17 fraternal pairs. All of the pairs included at least one twin that was a documented criminal. The study revealed in the group of 13 identical twins, 10 of the pairs both twins were criminals. In the group of 17 fraternal twins, only 2 of the 17 groups both of the twins were criminals (Adler, Mueller, & Laufer, 2008, p. 83). Due to the results of this study, although his techniques of study were limited at the time, it makes one wonder if in fact criminal behavior is an inherited behavior.
Other biological studies also included studies involved the study of children that were adopted. One of the largest studies conducted involving adopted children took place in Denmark between 1924 and 1947. This study consisted of 14,427 male and female adoptions. The purpose of this study was to determine whether an adopted child who came from a family consisting of at least adult criminal would also commit crimes. It also looked at whether an adopted child from a non-criminal family was adopted into a criminal family would the adopted child commit crime, and if a child adopted from a criminal family into a criminal family would commit crimes. The study revealed most the children who were adopted either from or into criminal families would eventually commit some type of crime (Adler et al., 2008, p. 85).
Studies were also conducted into the biochemical factors of crime; such as food...