The dominant liberal philosophy on which 19th century law reform was based -- that of the criminal as an independent, reasoning individual, consciously committing crime for calculated gain -- did not include women in its perspective. The two main theories of female criminality were deterministic. The first, deriving initially from evangelical penal reformers and later complemented by radicals such as Engels and Mayhew, held that women turned to crime following social or economic misfortune. The second theory, derived from the Victorian double standard in social and sexual activities, and receiving reinforcement from the concept of Social Darwinism, held that female crime was rooted in women's biological and psychological aberrations. Modern historical studies have tended to confirm the social deterministic position. Although female criminality has remained considerably less common than that of men, it does increase in response to certain conditions. Women who live in less restrictive, more anonymous urban environments, who are more independent of male protectors but more dependent on the labor market are more likely to turn to crime. If the social determinist position is correct, social policy should aim at changing the environment influencing women by eliminating poverty, inequality, unemployment, and sexism. A total of 71 footnotes are listed. (Author summary modified)