Objectives. To document criminality, psychiatric difficulty, IQ, EQ, and EI amongst Irish, male juvenile detainees (Detainee Group). To compare their IQ, EQ, and EI to non‐offending boys attending a child psychiatry clinic (Psychiatric Group) and boys without offending or psychiatric problems (Community Group). To compare psychiatric morbidity between the detainee and psychiatric groups. Method. Criminality levels of 30 detainees were evaluated using official court charge sheets. Psychiatric status was assessed through structured clinical interview (DISC‐IV); IQ through an individually administered IQ‐scale (WASI); EQ using the BarOn EQi:Youth Version (EQi:YV); and EI using the MSCEIT: Youth Version – Research Edition (MSCEIT:YV‐RE). IQ, EQ, and EI levels in the psychiatric and community groups were compared. Psychiatric morbidity between detainee and psychiatric groups were compared. Results. A total of 335 crimes led to the detention of detainees. Eighty‐three percent of detainees had a psychiatric disorder compared to 60% of young people in the psychiatric group. Detainees had 3.1 disorders each compared to 1.4 disorders in the psychiatric group. A total of 63.3% of detainees had an externalizing problem, 37.9% an internalizing problem, and 66.7% a substance dependency or use problem. A total of 21.4% of detainees had an IQ score below 70. The detainee and psychiatric groups had similar deficits in EI and significantly lower EI than the community groups. Conclusions. Serious levels of criminality and psychiatric disorder exist amongst Irish detainees. They have significantly lower IQ than young people attending a psychiatry clinic and both share deficits in the ability to accurately identify emotions, use emotions to guide thought processes and to prioritize thinking and to effectively regulate emotions.