Mental illness and intellectual disability in Magistrates Courts in New South Wales, Australia.
Adults with intellectual disability are far more common in court than in the community, and half also have mental illness, so BCBAs should screen for legal history and push for mental-health diversion.
01Research in Context
What this study did
Court staff in New South Wales gave quick IQ and daily-living tests to adults facing charges. They also checked police and clinic files for mental-health diagnoses. The goal was to see how many defendants had intellectual disability or low IQ plus mental illness.
What they found
One in three accused adults scored in the borderline or lower IQ range. Nearly half of that group also carried a mental-health diagnosis. The numbers show the court system holds far more people with these dual needs than the general public.
How this fits with other research
Luckett et al. (2002) argued that people with intellectual disability are under-represented in crime. Johnson et al. (2009) now show the opposite: they are over-represented in court. The gap is explained by method—T et al. looked at conviction rates while A et al. counted everyone appearing before a magistrate.
Griffith et al. (2012) extend the picture. They found that defendants with ID in mental-health courts receive more behavior and job help yet end with similar outcomes. Together the studies trace a path: identification in regular court (A et al.), then channelling to specialty court (M et al.) with little gain in final results.
Myrbakk et al. (2008) and de Kuijper et al. (2014) add why this matters—mental illness in ID often shows as aggression or screaming, behaviors that can trigger arrest. The court data now confirm those same symptoms land people in the justice system.
Why it matters
If you assess or support adults with ID, expect that jails and courts may see them first. Build screening questions about court history into your intake. When you see new aggression or screaming, think psychiatric referral before police referral. Push for diversion programs that link clients to mental-health care, not just probation.
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02At a glance
03Original abstract
BACKGROUND: Little is known about the prevalence of intellectual disability (ID) and/or cognitive impairment (CI) among accused persons in the Magistrates (Local) Courts, the personal, health and mental health characteristics of this cohort, and their service provision needs in the community. The study aimed to determine the prevalence of dual diagnoses of ID and/or CI and psychiatric disorder in a sample of accused persons appearing before four Magistrates Courts. Accused persons with ID and/or CI may not be identified in the Magistrates Court as having a disability and therefore may be unable to access the legal safeguards which exist for their protection within the criminal justice system and/or may fail to receive appropriate community health and welfare services. METHOD: The sample was drawn from accused persons aged over 18 years appearing before four Magistrates Courts in metropolitan and urban areas of a large city. Participants were assessed using the Kaufman Brief Intelligence Test, Second Edition (KBIT-2), Vineland Adaptive Behavior Scales, Second Edition (VABS2) and the Psychiatric Assessment Schedules for Adults with Developmental Disabilities Checklist. RESULTS: On the KBIT-2, 10% of participants achieved a standard score (SS) below 70 (mild ID range) and a further 20% were in the 70-79 (borderline) range. The VABS2 results indicated that 12% of participants had SS below 70 and a further 9% were in the 70-79 (borderline) range. The prevalence of mental illness in the group with intellectual deficits was 46%, compared with a prevalence of 36% for those without intellectual deficits. CONCLUSIONS: People with ID and/or CI were found to be over-represented in the Magistrates Court. Furthermore, results highlight the unmet mental health needs of this cohort in the criminal justice system. The results of the study have implications for the planning of services and diversionary options to facilitate better management of defendants with ID and/or CI with mental health needs.
Journal of intellectual disability research : JIDR, 2009 · doi:10.1111/j.1365-2788.2008.01148.x