Images of criminal law infuse our everyday lives. From newspapers and television news programmes reporting incidents or trials, to detective novels, films and television series such as The Bill, Law and Order, Silent Witness and The Wire, crime and the control of crime pour into our individual and collective consciousness. The images produced are complex and contradictory: heroic detectives compete for our attention with ‘bent’ police; wily criminals and informers jostle with the inadequate, the psychopath, the wife-batterer and even, on occasion, the offender with whom we are invited to sympathise; the dramatic appeal of racial injustice vies with the cultural resonance of racist stereotypes.

For many people who are neither practising lawyers nor legal scholars, criminal law represents the dominant image of what it is to have a legal system. In thinking carefully about the nature of criminal law, however, this familiarity can be an intellectual barrier. Most people's image of crime is dominated by crimes of violence or serious crimes against property, proceeded against through trial by jury. But in fact violent and sexual offences make up only a fifth of offences (and only half of violent offences involve injury). The reality of the criminal justice system is dominated by the processing of road traffic offences, minor public order and low-level property offences. Many never reach a court, having been diverted via fixed penalty notices or cautions (Young 2008).