It is suggested that individuals become criminals because of the presence of a persistent criminal identity. This has its origin in processes of negative social comparisons carried out by those who have failed in their pro-social roles and have exhibited non-conforming behaviour, aggravated and compounded by contextual factors such as a dysfunctional family environment and/or the presence of criminal peers. It is also suggested that development of a criminal identity might be influenced by representations of known criminals which are stored in memory system, and are made accessible due to relevant situational cues. This is consistent with the concept of multiple social identities which postulates that as a person’s social context changes, corresponding social identity changes are likely to occur as a result of the activation of situation-specific schemas. The potential role of personality is also indicated.