Crime is a social construct, and acts are only seen as crimes once society has reacted and decided they are offended by the behaviour.
Criminal is a label that police officers and judges have the power to attach.
Once an activity has been labelled as deviant, this label becomes attached to the indvidual.
This label overrides any other labels they may have and becomes their master status.
They find a sense of identity in this deviant subculture that they are denied in mainstream society due to their label, and then engage in a self fulfilling prophecy.