Eugenic laws mandating prevented unfit individuals from having children. These laws were grounded in Darwin 's theory of evolution and were eventually legitimized by the U.S. Supreme Court. The U.S. eugenic legal template was used by Nazi Germany to implement their own eugenic sterilization program, and through extension medical experiments, practices of euthanasia, and eventually the Final Solution. Dramatic evidence of four similarly legitimized medical experiments in the U.S. following World War II eventually resulted in a thoroughgoing bioethics movement, grounded in principles of autonomy, beneficence, and justice.