Psychiatric disorders in people with intellectual disability (intellectual developmental disorder): forensic aspects

Persons with intellectual disability come into frequent and underreported contact with the legal system. Advances in forensic psychiatry help better identify persons with intellectual disability in forensic contexts, inform evaluation and treatment, and elucidate unique characteristics of this population. With the release of Diagnostic and Statistical Manual of Mental Disorders (DSM-5), forensic psychiatrists must adjust to changes in the diagnostic process.

This review examines the past year's contributions to the literature, including predictors among offenders with intellectual disability, concurrent diagnoses, efficacy of competence restoration, means of studying individuals with intellectual disability, and impact of DSM-5.

Impoverished personal relationships are found to be an important predictor of offense among persons with intellectual disability. A Personality Disorder Characteristics Checklist allows screening for personality disorders (indicative of increased risk of violence) among intellectual disability offenders. Referrals to specialists for treatment more often occur for violent and sexual offenses than for other offenses. Competence restoration is historically low among those with intellectual disability, specially compared with those referred for substance abuse and personality disorders. However, the Slater Method results in higher rates of restoration than traditional training methods. DSM-5 alters the definition of intellectual disability, moving from an IQ-oriented diagnosis system to a multifaceted approach, introducing more flexibility and nuance.