An overlooked vulnerability in a defendant: Attention deficit hyperactivity disorder and a miscarriage of justice

Aim . To describe the implications of a Court of Appeal murder case involving a 15‐year‐old youth. His attention‐deficit hyperactivity disorder (ADHD) was not identified at trial, but 8 years later it was and his conviction was quashed. Method . An analysis of the judgments by the Court of Appeal at an earlier hearing (1997) and in 2004, together with a review of how the relatively new diagnostic concept of ADHD, can be employed to aid assessment of important vulnerable qualities. Results . One of the primary effects of ADHD in the case was to ‘affect’ the IQ scores, making it look as if the defendant was suffering from mental retardation and so masking his other more relevant vulnerabilities. Conclusions . ADHD symptoms are relevant to contended issues around adverse inferences and fitness to plead and stand trial. A comprehensive ADHD assessment, including neuropsychological testing, is necessary where there are indications of a history of childhood ADHD.