The participants were shown 150 slides on a laptop that displayed a variety of facial expressions - such as happy, sad, angry, afraid and disgusted - with varying degrees of intensity.
Following the intervention, the researchers found that both groups exhibited significant reductions in reoffending rates. However, the participants who took part in the emotion training also showed a significant reduction in the severity of the crimes they committed.
High severity crimes usually involve more physically aggressive behavior and interpersonal violence compared with less severe crimes, such as theft and criminal damage. The authors think, therefore, that because the emotion training worked on improving recognition of anger, sadness and fear, the offenders who took part in this training may have increased their understanding of the emotions of their potential victims, which dissuaded them from being physically aggressive or committing more severe crimes.