This study is focused on teenagers who behave violently and who are also victims of violence. The data was collected from records of adolescent inmates in São José do Rio Preto. The variables selected were: place of residence, age, education level, type of offense, drugs use, family income, parent education levels, jobs. The findings disclose a social and demographic profile for teenagers around seventeen years old with only elementary education. The most common offence was robbery; followed by theft, homicide, drug dealing, and robbery leading to death. Most of these teenagers smoked tobacco and marijuana, drank alcoholic beverages and took crack. The data indicate a context defined by precarious living conditions where family members have low incomes and poor job skills, together with alcohol abuse. As a result, they help turn teenagers into victims of society. The mother - who typically supports the household - is the strongest presence during the incarceration period, serving as a mediator between the adolescent in conflict with the law, the courts and the community. In view of the high costs of interpersonal violence, it is necessary to develop and implement a municipal strategy for children and adolescents in São José do Rio Preto.