Durkheim argues that deviance is useful for a society because it performs a variety of functions for society. It helps to clarify norms, it helps to unify groups, it helps to diffuse tension, and it helps to promote social change.
Deviance helps to clarify norms in a society because it helps to emphasize to people what is and is not acceptable behavior. When people act in ways that are unacceptable and they are punished, we learn that our society clearly believes that what they did is wrong. This helps us to know what is right and wrong (in our society).
Deviance helps to unify members of a group. What this means is that the actions of deviant individuals helps to unify people who are not deviant. The people who are not deviant see the deviant behaviors and they react against them. They form an “us against them” attitude with respect to the deviants. This reinforces their connections with the “good” people in the society.
Deviance diffuses tensions. It can help to serve as a safety valve for people who are unhappy with their society or with the norms of their group. For example, if children are somewhat unhappy with the rules that their parents set, they might act out in small ways. This relieves some of their anger and makes it so they do not challenge the main rules and norms of the family.
Finally, deviance can promote social change. It can show what areas are problematic in a society or group. People in power might notice deviant behavior and work to correct the problems that lead to that behavior.
In these ways, deviance can be beneficial to a society.