ADHD & Criminal Justice: Understanding the Iceberg

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The prevalence of Attention Deficit Hyperactivity Disorder (ADHD) among people in the Criminal Justice System is believed to be around ten times that of the general population, with around 25% of adults in prison having ADHD compared to 2.5% of adults in the general population (Young & Cocallis, 2021).

Given the high prevalence of ADHD in police stations, prisons and Crown court docks, understanding the condition’s possible impact upon fairness and participation is essential. This need has been recognised by the Ministry of Justice, whose 2021 Prisons Strategy White Paper underscored the need for greater understanding and adjustments for prisoners with ADHD (in response to the 2021 Neurodiversity in the Criminal Justice System report).

Beyond inattention

A big part of understanding and making adaptations to accommodate ADHD more effectively is going beyond the surface. Views on ADHD vary, with some dismissing the condition as ‘naughty child syndrome’, while others understand it to be simply a matter of inattention. In fact, ADHD is a much larger cluster of traits and difficulties.

It can be helpful to picture an iceberg, with a handful of well-known ‘visible’ symptoms (like fidgeting and difficulty paying attention) at the top. A much larger portion of the iceberg, however, is hidden underwater. Here, a much larger number of possible difficulties can be found, including difficulty inhibiting behaviour, difficulty retaining information in order to make a decision, difficulty planning and difficulty regulating emotions.

Picture of an iceberg. The most obvious ADHD symptoms are above the water (inattention, distractibility, restlessness). The lesser known (or hidden) symptoms are below the water (inhibitory control, emotional regulation, social skills, working memory, executive functioning).

On a number of occasions during court hearings, I have encountered legal professionals who are not cognizant of the ADHD iceberg. This means that they may be aware of the overt symptoms of ADHD, but unaware of the less well-known and recognisable impacts of the condition. For this reason, I have sometimes encountered judges who have been accommodating in terms of permitting regular breaks, but less disposed to implementing recommendations around how written evidence is used during the evidence of a defendant with ADHD (in this instance, the defendant had considerable difficulty switching his focus when asked to read written evidence on the stand, then struggled to hold information from that document in his mind when answering questions arising from it).

Under the surface

A growing body of research has been exploring the impact of ADHD at all stages of the criminal justice system, from first police interview to rehabilitation.

In police interviews

  • ADHD is associated with a threefold increase in previous reported false confessions (Gudjonsson et al., 2008).

  • ADHD is associated with increased compliance, which means an individual is more likely to submit to a request or demand(Gudjonsson et al., 2008).

  • ADHD can make it difficult for people to manage their emotions and responses during police interviews (Gudjonsson, 2010).

  • Police can divert from best practice interview approaches when interviewing someone who presents with ADHD-like symptoms. This can lead to poor or inadmissible interviews (Cunial et al, 2018).

  • “People with ADHD have been shown to apply maladaptive coping strategies when faced with stress, which are comprised of confrontation, escape-avoidance and lack of planning in problem-solving(Gudjonsson, Young & Bramham, 2007).

  • People with ADHD are more likely to answer “don’t know to questions put to them in police interview (Gudjonsson, Young & Bramham, 2007). This can be perceived as evasive, dishonest or unhelpful by both interviews and courts when a case comes to trial.

  • People with ADHD are especially likely to experience heightened discomfort and difficulty in police custody (Gudjonsson & Young, 2006).

At court

The Royal Courts of Justice. Image credit: David Castor

During court proceedings, issues with attention, compliance, emotional management, executive function [LO1] (e.g. short-term memory, inhibiting impulses, switching tasks, planning and organisation) may all negatively impact a defendant’s ability to understand legal advice, give clear instructions, understand legal argument, follow the thrust of evidence and to give evidence themselves (if they choose to do so). Brown et al. (2022) found that “the prevalence of mental illness and neurodevelopmental disorders in defendants is high. Many are at risk of being unfit to plead and require additional support at court, yet are not identified by existing services”.

The case of R v Friend (1997) offers a window into some of the difficulties a defendant with ADHD may face at trial. In this case, Mr Friend’s legal team argued that adverse inference should not be drawn from his decision not to give evidence at court because “the physical or mental condition of the accused makes it undesirable for him to give evidence”. The judge disagreed and ruled that the jury could draw adverse inference. The case was appealed and the conviction ruled unsafe, after the court of appeal heard from Dr Susan Bailey (an expert in adolescent psychiatry). She stated that it would have been undesirable for Mr Friend to give evidence, as he may have…

  • struggled to maintain attention over a prolonged period.
  • become easily distracted.
  • lost focus and thought about irrelevant topics.
  • ‘tuned out’ and missed chunks of proceedings.
  • lost his train of thought during evidence.
  • ‘blurted out’ the first response which came to his mind.
  • become emotionally labile, distressed or angry.
  • struggled to inhibit a verbally aggressive response.

In prison

Image: Derek Harper and licensed for reuse under this Creative Commons Licence.
  • People in prison who have ADHD are more likely to be involved in incidents of verbal aggression, physical aggression, damage to property, self-injurious, arson and ‘other’ behaviours” (Young et al., 2009).

  • “Once in a custodial environment, offenders with ADHD can present a management problem as their symptoms are reportedly associated with aggressive behaviours […] most likely due to their emotional lability and behavioural disinhibition (Young, 2013).

  • ADHD has many common co-morbidities, particularly conduct disorder and substance use. Vélez-Pastrana (2020) notes that “ADHD complicates and exacerbates the mental health needs of prisoners and thus requires treatment approaches that respond to this complexity”. 

On probation

© Copyright Jaggery and licensed for reuse under this Creative Commons Licence.

Probation is a crucial step in an individual’s journey out of the criminal justice system. However, tackling recidivism in people with ADHD may be more challenging. For many there is little in the way of ‘joined up’ services. Those who are diagnosed with the condition in prison, for example, may leave prison with enough medication for a week, then receive no support and a long wait to restart medication which they have found helpful.

Difficulties with impulsivity and executive function may also make it particularly challenging for someone with ADHD to follow any conditions attached to their probation. In a study conducted into ADHD in probation caseloads (Young et al, 2014), probation staff…

  • underestimated ADHD in their caseloads.
  • felt service users with ADHD had problems with compliance, motivation and engagement.
  • felt that available interventions were often not sufficient or not suitable.
  • wanted more support and training to work with offenders with ADHD.

Looking forward

Although not comprehensive, these ideas and statistics paint a picture of some of the negative impacts ADHD can have on an individual’s participation and access to justice at key stages in the criminal justice system. With greater attention now being paid to the condition in this setting, there is hope for the implementation of quality screening for ADHD in police stations and prisons, more joined up services from prison to the community and more interventions for individuals in prison with ADHD (e.g. medication and therapy). These are all important goals which could have a marked positive impact in a range of areas, from recidivism to equal access to justice.

The intermediary role

There is also hope that courts will become increasingly aware of the varied ways in which ADHD can impact effective participation during court proceedings. When we assist service users with ADHD, our intermediaries work hard to clearly outline the possible impacts of ADHD to the court. We also strive to provide clear, practical and measured recommendations which will help to mitigate the difficulties ADHD may present, from seating the defendant outside of the dock to ensuring questions are short, simple and direct during their evidence.

Our intermediaries also identify and implement strategies to facilitate the participation of court users with ADHD outside of the courtroom, for example during legal conferences and assessments.

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For more information about how an intermediary can assist a defendant with ADHD, or to learn more about how to arrange an intermediary, contact the Communicourt operations team.

Learn more about court communication from experienced court intermediaries on The Access Brief. A growing library of free resources developed for legal professionals working with clients who have communication needs.


Brown, P., Bakolis, I., Appiah-Kusi, E., Hallett, N., Hotopf, M., & Blackwood, N. (2022). Prevalence of mental disorders in defendants at criminal court. BJPsych Open, 8(3), E92. doi:10.1192/bjo.2022.63

Criminal Justice Joint Inspection. (2021) Neurodiversity in the Criminal Justice System, A review of evidence. London.

Cunial, K., Casey, L., Bell, C., & Kebbell, M. (2018). Police perceptions of the impact that ADHD has on conducting cognitive interviews with youth. Psychiatry, Psychology And Law26(2), 252-273. doi: 10.1080/13218719.2018.1504241

Gudjonsson, G. H. (2010). Psychological vulnerabilities during police interviews. Why are they important? Legal and Criminological Psychology, 15, 161–175

Gudjonsson G, Clare ICH, Rutter S, Pearse J. (1993) Persons at Risk during Interviews in Police Custody: The Identification of Vulnerabilities. Royal Commission on Criminal Justice Report. Cmnd.2263. London: HMSO; 1993. 

Gudjonsson, G., Sigurdsson, J., Bragason, O., Newton, A., & Einarsson, E. (2008). Interrogative suggestibility, compliance and false confessions among prisoners and their relationship with attention deficit hyperactivity disorder (ADHD) symptoms. Psychological Medicine38(7), 1037-1044. doi: 10.1017/s0033291708002882

Gudjonsson, G., Young, S., & Bramham, J. (2007). Interrogative suggestibility in adults diagnosed with attention-deficit hyperactivity disorder (ADHD). A potential vulnerability during police questioning. Personality And Individual Differences43(4), 737-745. doi: 10.1016/j.paid.2007.01.014

Ministry of Justice. (2021). Prisons Strategy White Paper. London.

R v Friend [1997] 1 WLR 1433; [1997] 2 All ER 101; [1997] 2 Cr App R 231; [1997] EWCA Crim 816.

Young, S., Goodwin, E., Sedgwick, O., & Gudjonsson, G. (2013). The effectiveness of police custody assessments in identifying suspects with intellectual disabilities and attention deficit hyperactivity disorder. BMC Medicine11(1). doi: 10.1186/1741-7015-11-248

Young, S., & Gudjonsson, G. H. (2006). ADHD symptomatology and its relationship with emotional, social and delinquency problems. Psychology, Crime & Law, 12(5), 463–471.

Young, S., Gudjonsson, G. H., Goodwin, E. J., Jotangia, A., Farooq, R., Haddrick, D., & Adamou, M. (2014). Beyond the Gates: Identifying and Managing Offenders with Attention Deficit Hyperactivity Disorder in Community Probation Services. AIMS public health1(1), 33–42.

Young, S., Gudjonsson, G. H., Wells, J., Asherson, P., Theobald, D., Oliver, B., et al. (2009). Attention deficit hyperactivity disorder and critical incidents in a Scottish prison population. Personality and Individual Differences, 46(3), 265-269. doi

Vélez-Pastrana M, C, González R, A, Ramos-Fernández A, Ramírez Padilla R, R, Levin F, R, Albizu García C. (2020) Attention Deficit Hyperactivity Disorder in Prisoners: Increased Substance Use Disorder Severity and Psychiatric Comorbidity. Eur Addict Res 2020;26:179-190. doi: 10.1159/000508829