Varying crime rates were explained by the cultural conflict approach and the process by which individuals became criminal was expressed by the symbolic interactionism approach. Thus, he formulated his theory with an attempt to explain not only individual criminal behavior but also those of societal groups. Sutherland argued that people learn definitions over the life course and that they are exposed to these definitions in systematic ways. So his theory is ultimately a cultural conflict theory at the individual level because norms and values are learned which then lead to corresponding behaviors. Criminal behavior is learned.
Criminal behavior is learned in interaction with others persons in a process of communication.
The principal part of the learning of criminal behavior occurs within intimate personal groups. When criminal behavior is learned, the learning includes techniques of committing the crime, which are sometimes very complicated, sometimes simple and the specific direction of motives, drives, rationalizations, and attitudes. The specific direction of motives and drives is learned from definitions of the legal codes as favorable or unfavorable. A person becomes delinquent because of an excess of definitions favorable to violation of law over definitions unfavorable to violation of the law. Differential associations may vary in frequency, duration, priority, and intensity.