Sociology has several theories about crime and deviant behavior to explain why such behavior occurs. Deviant behavior is any behavior against the norms of society, including criminal behavior, explains sociologist and writer Ashley Crossman in an About.com article.
According to Crossman, sociologist Robert Merton proposed the structural strain theory. It states that tension is due to a gap between cultural goals and the individual's means to achieve such goals. Merton classified people into general categories concerning culturally accepted goals and how to achieve them. His groups included conformists, ritualists, innovators, retreatists and rebels. Innovators, who accept cultural goals but reject conventional means of obtaining them, are those society regards as criminals.
Travis Hirschi's social control theory attributes deviance to a weakened sense of attachment to social bonds, explains Crossman. This theory sees people as conforming to social expectations due to their concern about what others think. It looks at what breaks a person's commitment to such values and indicates that while everyone has tendencies toward deviance, most do not act on these tendencies because of an attachment to social norms.
The theory of differential association explains deviant behavior by focusing on the processes that lead people to criminal acts. Crossman attributes the theory to Edwin H. Sutherland, who says deviants learn criminal behavior through their interactions with others. It looks at peers and others in one's environment and focuses more on the how and not the why.