Eugenics became popular during the 1920s. Eugenics was a movement that advocated to improve the genetic disposition of a population. During this time, people who were deemed to be imbeciles or feeble-minded would be sterilized. It is a practice that sought to improve the human race by reproduces only desirable traits.
The most famous case was the Buck vs. Bell of 1927, where a 17 year old Carrie Bell was deemed feeble-minded, because her mother was said to be loose because she did not know Carrie's father. Psychologist and doctors tested Carrie's mother Emma and decided that there was definitely something wrong with her and that her traits should never be passed along. Carrie who has an illegitimate child is also deemed loose and feeble-minded by doctors, although they could not report what exactly was wrong with her. The jury and Supreme Court agreed that they should be steriized for the good of man kind, one juror, Oliver Wendell Holmes said, "3 generations of imbeciles are enough." The people of this time truly believed that they were doing good by sterilizing people who were blind, mute, epileptic or disabled in any other way. Some psychologist were disappointed because they didn't believe that enough was being done.
Interesting enough, the same thing happened in Germany in period leading up to the Holocaust. The most desirable traits were blond hair and blue eyes and the Nazis sought to pass this look on, as it was the look of the most evolved human, in their eyes. When the Nazi's began to take people away to concentration camps, they did not target Jews alone. They targeted Africans, Gypsies, twins (because this was seen as a defect), the blind, deaf, mute, handicapped, and gays, because these were all things that they believed would hold back the evolution of the human race.