Lombroso manifested the school of criminology known as the Positive School, who searched through scientific research and experimentation for the explanation of criminal behavior. The Positive Schools primary focus was on the prevention of crime and the reformation of offenders, the demand for facts and scientific proof and that there are mind and body differences between people and that the punishment should fit the individual criminal, not the individual crime. He believed that the justice system should be technocratic and all criminals can be treated, if not then they should be put to death. .
Lombroso was a follower of Gall, Darwin and Lavater and became convinced that a criminal man was an immoral person. He called the "born Criminal" a being that was predestined for criminal behavior due to his physical configuration. Compiled with a list of characteristics including short or tall in height, small head but large face, a small and sloping forehead, a receding hairline, wrinkles on the forehead and face, large sinus cavities or bumpy face, large protruding ears, bumps on the head particularly the destructiveness center behind the ear, bushy eyebrows, high cheek bones, large eye sockets, thin neck , beady eyes, abnormal teeth, small or weak chin, strong jaw line, fleshy lips but thin upper lip, sloping shoulders but large chest, webby, pointy, stubby fingers or toes, long arms, tattoos on body, and beaked or flat noses were known as criminal indicators. Another point the school made was that there were four classes of criminals: born (atavists), insane, occasional (criminaloids-with some atavistic characteristics and some environmental factors) and passion.
The "born criminal" descended from a degenerate family with cases of insanity, deafness, syphilis, epilepsy and alcoholism among its members. The "born criminal" was easily identified by certain characteristics known as "stigmata".