"Emile Durkheim upset a lot of people, back in the late 19th century, by claiming that there was a “normal” rate of crime, which society seeks to maintain. He argued that the apprehension and punishment of criminals served a social function, by reaffirming everyone else’s commitment to the social order. In the same way that public rituals serve as a reaffirmation of faith for members of certain religion communities, the punishment of criminals plays the same role for members of society more generally. We find it easier to do our part in maintaining the social order when we have visible evidence that those who fail to do so are being appropriately sanctioned."
"This is why the general public takes such a keen interest in the punishment of criminals, and much less in, say, road maintenance, even though with the division of labour, there are agents of the state whose job it is to make sure that each is done expeditiously. But in order for this reaffirmation of the social order to take place, there must first be a sufficient number of criminals. This is where the “normal” rate of crime comes in – this is the level that is functionally required to maintain social solidarity. Durkheim argued that the crime rate cannot really drop much below this normal level, because if it does, society will respond by criminalizing new forms of behaviour, in order to bring the rate back up."