1880-1925

During this period, a popular belief was that mental retardation and mental illness were completely genetic, and caused most, if not all, social ills such as poverty, drunkenness, prostitution, crime, and violence. The response to this belief was to segregate or sterilize people who were labeled mentally retarded or mentally ill so that they could not reproduce and destroy the gene pool.

Pictures of people who committed arson, murder, or other acts of violence were often drawn in newspapers to suggest the presence of mental retardation. As late as 1920, the Public Health Service combined "criminals, defectives, and delinquents" into a single category.  (http://www.mnddc.org/parallels/four/4d/7.html)