Young people aged 10 to 24 are particularly involved in criminal cases dealt with by the courts: they represent 21% of those over the age of 10 but 36% of presumed perpetrators of criminal offences. In 2014, these young people involved with the justice system represented 5.2% of their age group.

Theft and handling stolen goods (25%) and drug offences (17%) are the two main types of offence involving young people, followed by deliberate assaults (15%) and road traffic offences (15%).

For each offence, the numbers of perpetrators peak at a certain age: sexual attacks are more common at 14, theft and violence at 16, drug offences at 18 and road traffic offences at 22. Thus the structure of offences changes with age, becoming more diverse and with a growing proportion of road traffic offences.

While the change in offences is gradual, the response of the criminal justice system changes radically at the age of 18 when young people switch into the adult system. On the one hand, there are fewer alternative procedures for young adults than for minors (44% and 63% of the response of the criminal justice system respectively). On the other hand, prison sentences (not suspended) are more common for adults, while educational measures, which are only available to minors and which are the predominant sanction, give way to fines.

Juvenile delinquency is not a marginal phenomenon: 21% of men and 3% of women of the generations born in 1986 and 1987 have been sentenced at least once for offences committed between the ages of 10 and 24.