Studies on criminality (Elliot, 1994; Farrington, Lambert, & West, 1998; Loeber et al. , 1999) agree on the onset and escalation of criminal offending during early adolescence, peaks during late adolescence, and gradually declines in early adulthood. These show the common trend in different countries or regions, historical periods, and across gender and race. Age is a strong determinant of criminality.
There are three key periods in the progression of offending, which are commencement or onset, peak, and decline. The onset period is important in developing preventive measures. The peak period is the key to identifying responses to risk groups. The period of decline reflects on the de-motivation for continuing offending in adulthood and reflects on the effectiveness of existing interventions. Understanding the dynamics of these periods are equally important in responding to offending.
The causes of juvenile offending that accounts for the onset and progression of offending during early adolescence are well known and encompasses biological, psychological, economic and sociological explanations. However, the reasons for the decline in offending still involve divergence in perspectives. Nevertheless, the expansion of the reasons for the onset could also extend to the decline. Psychological theories covers the link between age and the periods of offending. The discussion covers these theories as explanations for the onset, peak and decline of offending.