The development of aggression and its linkages with violence and youth delinquency

Over the past decade studies of the development of violent juvenile delinquency have gained momentum. Large prospective longitudinal studies on different continents have shown the potential for a developmental approach to clarify the developmental course, determinants and malleability of violent delinquent behaviour by juveniles.

However, notwithstanding these accomplishments, one may wonder to what extent the potential benefits of a truly developmental approach have been brought to fruition to date. Based on a critical review of the literature, three major issues are identified: (1) prospective research has been highly explorative rather than hypothesis testing; (2) development has been described in terms of mean changes with age or static patterns rather than in terms of individual trajectories; and (3) there has been a strong focus on correlates and risk-factors instead of on causal mechanisms driving development. Suggestions are made to resolve these issues by formulating clear developmental theories to be tested with longitudinal experimental studies of individual developmental trajectories, their malleability, and mediators of change.