 By the 1920s, many U.S. states brought in laws permitting the compulsory sterilization of people considered genetically unfit, including inmates of prisons and psychiatric hospitals.This was followed by similar laws in Germany, and throughout the Western world, in the 1930s.Under the influence of determinist beliefs, the American craniologist Samuel George Morton (1799–1851), and later the French anthropologist Paul Broca (1824–1880), attempted to measure the cranial capacities (internal skull volumes) of people of different skin colours, intending to show that whites were superior to the rest, with larger brains.