Childhood acquired brain injury (ABI) is responsible for severe cognitive and behavioural disorders, sometimes leading to violent and/or offending behaviours. The aim of this study was to review the cases of patients treated in a rehabilitation unit dedicated to children with ABI, who subsequently demonstrated behaviors leading to an intervention of the police and/or the justice, and identify any common characteristics. Retrospective inventory of patients with ABI treated in a single rehabilitation department, who subsequently had contact with the police/justice following offenses. We collected demographic factors, type and severity of ABI, initial neurological examination, first and last neuropsychological assessment, type of schooling pre- and post-injury, and data from their offenses. Searches retrieved 40 patients (36 boys): 34 traumatic brain injury (TBI; 27 severe), 4 brain tumours, 1 frontal hemorrhagic stroke and 1 anoxia; mean age at injury was 9.7 years [SD = 4; (2.1–15.7)]. In 88% of cases, none of the parents had graduated from high school. Half of the children had previous school difficulties and 30% had repeated a grade. Overall, children sustained severe injuries, with impaired neurological function, major cognitive deficits [mean initial full-scale IQ 73.1 (SD = 12.8)] without significant improvement [77.4 (SD = 13.4) at the last assessment]. The processing speed index was particularly low [73.2 (±15.4)] and did not improve over time. 76% had behavioural disorders already evident during hospitalization. Upon discharge, 62% required adapted and/or specialized schooling. After an average follow-up of 8 and a half years, only 6 patients still followed an ordinary curriculum and 8 were not attending school anymore. Four girls were victims, and among 36 boys, all were perpetrators, but 3 had been victims previously. The offenses were mainly cases of violence (56%), but also entailed thefts, traffic offences, sexual assaults, drug use and vandalism. Children with ABI who suffer or commit offenses are mainly boys, from very low socioeconomic background, with pre-injury academic and social difficulties, who sustained severe TBI. They suffer very severe and disabling cognitive deficits and behavioral disorders. Multidisciplinary care and follow-up of those children more at risk is essential in the long-term.