Recent event-related potential (ERP) studies indicate that antisocial and psychopathic behavior is in some circumstances characterized by heightened attentional processes. This prospective study assesses whether ERP measures of attention recorded in adolescence are capable of predicting criminality status in adulthood. N1, P300, and contingent negative variation (CNV) were recorded during a CNV paradigm in a representative sample of 101 male schoolchildren at age 15, and related to criminality status at age 24. Criminals-to-be were characterized by larger N1 amplitudes and faster P300 latencies to the warning stimulus. Psychopathic personality within the criminal group was associated with larger N1 and CNV amplitudes. A discriminant function analysis using N1 and P300 measures correctly classified 74% of cases. It is concluded that enhanced early attentional processing may be of etiological significance in the development of criminality and that ERP measures may be of value in the early prediction of criminal behavior.