Definition
Differential association is the proposition that criminal behaviour is learned, in the same way any other behaviour is learned, through interaction in small intimate groups. A person becomes likely to offend when their exposure to definitions favourable to violating the law outweighs their exposure to definitions unfavourable to it.
Edwin Sutherland set out nine propositions in successive editions of his Principles of Criminology (1939, 1947). The theory was a deliberate rejection of biological and psychological accounts: offending was not a defect of the individual but the output of an ordinary learning process operating in particular social environments. It became the seed for later social-learning, sub-cultural, and gang theories.
Why it matters
How it works
Learning includes the techniques of the offence, the motives, the rationalisations, and the attitudes that legitimate breaking specific laws. What matters is the balance: more frequent, longer, earlier, and more emotionally intense exposures to pro-crime definitions tip the calculus. The mechanism is symmetric — the same process explains conformity when the dominant definitions favour the law.
Critics note that the theory is hard to operationalise (how do you count "definitions"?), and that it underplays structural conditions that produce the peer networks in the first place. Later social-learning theorists, especially Ronald Akers, retained the core mechanism while bolting on reinforcement and modelling from behavioural psychology to make the predictions testable.