Views And Reviews

Autism is underdiagnosed in prisoners

BMJ 2016; 353 doi: (Published 02 June 2016) Cite this as: BMJ 2016;353:i3028
  1. Sarah Ashworth, forensic psychologist in training1 2
  1. 1Centre for Forensic and Family Psychology, University of Nottingham
  2. 2Derbyshire Autism Services, Ripley
  1. lwxseash{at}

More investment is needed for assessment in forensic settings

The UK government strategy on autism spectrum disorder (ASD) now refers to prisoners,1 an improvement on the previous lack of focus. However, despite over-representation of ASD in forensic settings (0.98% of the general population but 2.3% in secure forensic settings),2 3 only five of the 33 action points consider forensic populations.

ASD is of specific concern among prisoners because it can slip through the gap between learning disabilities and mental health diagnoses, for which more formal assessments, in addition to liaison and diversion schemes, are being developed in forensic services. Identification of ASD at the earliest possible stage in the criminal justice system could allow for better assessment and management of challenging presentations, minimise the risk of additional mental ill health developing in this population, highlight the need for specialist support and services, and ultimately reduce the risk of reoffending. Despite UK legislation that promotes assessment of and support for ASD,4 5 a more systematic approach is needed in forensic settings.

The National Institute for Health and Care Excellence (NICE) in England and Wales sets a three month maximum waiting time between referral for diagnostic assessment for ASD and the first appointment. On average, adults wait two years.6

Diagnosis crisis

This “diagnosis crisis” is likely to be even worse for prisoners who are vulnerable by nature of incarceration. In the criminal justice system, not only may the waiting time be unacceptably long but diagnosis may be overlooked altogether despite observable clinical indicators.

Several factors contribute to missed diagnoses. ASD may be masked, where the associated rule adherence behaviour creates minimal problems in managing such prisoners. Staff may miss ASD because of poor understanding of its presentations,7 resulting from inadequate training.8 Even if ASD is suspected, prisoners may not be referred to specialist services for diagnosis because staff are unaware of the benefits or how to refer, or because resources are lacking.

This also applies in police custody, where the Police and Criminal Evidence Act requires that prisoners suspected of having ASD have an appropriate adult present.9 Failure to provide statutory assessment means that this population may not be recognised and that their additional needs remain unmet.

Even if a prisoner comes to the attention of healthcare professionals, NICE recommends that diagnosis should be informed by a detailed neurodevelopmental history. This is often difficult to obtain in forensic populations.

Additionally, diagnostic instruments are often time consuming and costly, limiting their use in prison populations in austere times. To overcome this problem with other mental health disorders, quicker (cheaper) screening tools have been used in prisons,10 but no such tool is employed systematically for ASD. Although general mental health screening has helped prison staff,10 they need specialist training in ASD and in the pathway for referral and assessment.

Psychiatric comorbidity

A lack of diagnosis affects analysis of offences and the development of risk management plans, as well as awareness of prisoners’ increased vulnerability to bullying or exploitation, their heightened risk of psychiatric comorbidity, and the management of challenging behaviour resulting from deficits in social and communication skills.

These problems are costly in themselves. Inadequate risk management and subsequent reoffending may well cost more than ASD assessment and support, financially and in terms of public safety.

More ringfenced investment is needed for diagnostic assessment in forensic settings. The hidden population of prisoners with ASD deserve our attention, for their own care and for public safety. Future harm may be avoided if an offender receives the specialist ASD support required to help manage the risk of reoffending.


  • I thank Ruth J Tully, consultant forensic psychologist and assistant professor at the Centre for Forensic and Family Psychology, University of Nottingham, who supervised my writing of this article and is guarantor.

  • Competing interests: I have read and understood BMJ policy on declaration of interests and declare that we have no competing interests.

  • Provenance and peer review: Not commissioned; not externally peer reviewed.


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