Abstract
Effective participation in trial is outlined under article 6 of the European Convention on Human Rights and refers to the ability to understand and engage in trial. Juvenile defendants are often referred to psychologists or psychiatrists by their solicitors to establish ‘effective participation’ capacity. In the USA, key components to participate effectively are defined and standardised assessments available. In the UK, no formal measures exist. A consecutive series of 20 adolescents aged 12–20 years, referred by their solicitors to our service, were assessed using a standardised battery and a semi-structured interview designed to assess effective participation. Fifty-five per cent had at least one neurodevelopmental disorder. Low IQ was common and 50% had age-equivalent language scores below 10 years. Rates of depression, anxiety and PTSD were high. Knowledge about trial was poor. These findings have implications for Criminal Justice System professionals and to ensure fair trials for young defendants.