The general public seems to be convinced that juvenile delinquency has
massively increased over the last decades. However, this assumption is much less popular
among academics and some media where doubts about the reality of this trend are often
expressed. In the present paper, trends are followed using conviction statistics over 50 years,
police and victimization data since the 1980s, and self-report data collected since 1992. All
sources consistently point to a massive increase of offending among juveniles, particularly
for violent offences during the 1990s. Given that trends were similar in most European
countries, explanations should be sought at the European rather than the national level. The
available evidence points to possible effects of increased opportunities for property offences
since 1950, and although causality remains hard to prove, effects of increased exposure to
extreme media violence since 1985.