Serum testosterone in violent and nonviolent young offenders.

Single morning serum testosterone samples from 194 15-17 year old male young offenders were compared between subgroups based on violent (n = 75), non-violent (n = 102), and sexual (n = 17) offenses. The violent group had the highest level of testosterone and differed significantly from both the nonviolent and sexual offender groups which were statistically equivalent. The offenders were also classified according to native/metis (n = 68) and Caucasian (n = 126) groups, and the native/metis group had significantly higher testosterone than the Caucasian group. Higher testosterone in the native/metis group may be because this group committed significantly more violent offenses than the Caucasian group. Genetic factors, such as the human leucocyte antigen system, may also be associated with higher testosterone in the native/metis group.