Traumatic Brain Injury and Juvenile Offending: Complex Causal Links Offer Multiple Targets to Reduce Crime : The Journal of Head Trauma Rehabilitation

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Traumatic Brain Injury and Juvenile Offending

Complex Causal Links Offer Multiple Targets to Reduce Crime

Williams, W. Huw PhD; Issue Editor; McAuliffe, Karen A. PhD; Cohen, Miriam H. MSc; Parsonage, Michael MA; Ramsbotham, John GCB, CBE, MA

Editor(s): Williams, Huw PhD, D Clin Psych

 General The Lord David

Author Information
Journal of Head Trauma Rehabilitation 30(2):p 69-74, March/April 2015. | DOI: 10.1097/HTR.0000000000000134
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TRAUMATIC BRAIN INJURY (TBI) is a leading cause of death and disability in children and young adults1 and is widely acknowledged to pose major global health and social challenges.2 This article deals with the accumulating evidence that TBI is associated with criminal behavior.3 This topical issue contains studies that demonstrate that children who survive TBI are likely to become adults with behavioral problems,4 that young people with TBI being adjudicated may have poor levels of communicative ability5 that could place them at a disadvantage in legal proceedings, that the rates of TBI are very high in offender groups,6 and that TBI is linked to psychiatric disturbance—particularly self-harm.7 These studies indicate that TBI is an endemic chronic health condition in offender populations and may well be a factor that contributes to the risk of criminal behavior. These studies raise the troubling possibility of a “double hazard” by which children who are socially disadvantaged and who experience a TBI are at increased risk of worse outcomes.8 Furthermore, poor social-communication skills may increase the chances of externalizing behaviors that eventuate in criminal acts such as aggression against others. In this article, we argue that screening for, and managing, the effects of TBI may improve the well-being of affected young offenders and—potentially—reduce crime.


The links between TBI and criminal behavior are complex. Young people who offend likely do so for many reasons—genetics, disadvantage, abuse, antisocial personality, peer pressure, among others. It is difficult to identify a clear causal link between TBI and offending. Adolescence is marked by increased “risk taking” and is thus a “life stage” during which risky behavior may foster a drift toward criminal action that may persist throughout a lifetime.9 Traumatic brain injury is more common among young people who take risks, especially in adolescence. Therefore, TBI may be coincidental to such risk taking, that is, those who offend may do so whether or not they sustain a TBI.

However, it does appear that TBI alters one's life trajectory so as to increase the chances of offending. In a Finnish birth cohort study of approximately 12 000 subjects, a TBI during childhood or adolescence was associated with a 4-fold increased risk of mental disorder, with coexisting offending in adult males.10 Crime histories tended to occur following TBI. Even more compelling evidence for links between TBI and crime come from a Swedish total population data linkage study. Fazel et al11 showed that 8.8% of those with TBI committed violent crime compared with 3% of controls. Of note, risk was still greater among TBI cases than among siblings who presumably experienced the same social and environmental conditions as their related offender. Furthermore, a history of loss of consciousness among offending youth has been linked to persistent, rather than adolescent-limited, offending.12

Once a person's life course is on a downward trajectory, with an increased likelihood of incarceration, does a TBI matter? It certainly matters in venues where justice systems lack resources to recognize or manage TBIs. Studies from across the world have shown that the rate of TBI is much greater—3 to 8 times as high—in offender populations than in nonoffender groups.6 Studies have also shown that about half of young offenders have a history of loss of consciousness, with repeated injuries being very common.13 Traumatic brain injury in offenders has been associated with higher rates of infractions while in custody, higher levels of reoffending, and engagement in violent crimes.9,14–18 It would therefore appear that managing the effects of TBI may be important both for improving engagement in forensic rehabilitation and for limiting recidivism.


There are various ways in which a TBI might increase the likelihood of problematic—even criminal—behavior. Traumatic brain injury can cause impairment of attention, planning, memory, language, and visuospatial processing, as well as having detrimental effects on mood and behavior. From the studies in this issue, a consistent theme emerges: that TBI, across levels of severity, can compromise key neural regions important for acceptable social behavior.

Moderate to severe TBI is typically characterized by pathology in anterior brain regions as well as diffuse white matter injury. Milder forms of TBI can produce brain changes, such as inefficiency in brain systems due to loss of conduction in white matter tracts.19 Such effects are particularly evident where injury is repeated.20,21 It appears that brain systems most vulnerable to such TBIs comprise the “social brain network.”22 These systems not only serve self-regulation—planning, initiation, inhibition—but also promote the process of deducing emotions from facial expressions and tone of voice. At an integrative level of cognition, systems vulnerable to TBI allow us to “read” others' minds for intentions and to feel an empathic response.23 During childhood and adolescence, these systems are maturing and becoming modularized.24 Injury could interrupt the development of these vital systems for self-regulation and social interaction, with likely increased risk of poor decision making, impulsive aggression, and lack of control of social behavior. Indeed, persistent offenders are often described as impulsive and lacking affective empathy, consequences that may be linked to deficits in “social brain systems.”25,26

There is growing evidence of brain injury pathology in these brain systems in offenders.27–30 For example, Schiltz and colleagues31 found that violent prisoners had many more neurological abnormalities—typically in frontal areas—on brain scans than nonviolent and nonoffending controls.

Of course, the causal link between crime and such pathology is complex. Presence of frontal brain pathology may well be evidence of a TBI, but we need to be cognizant of the possibility of a role for preinjury neurogenic factors. A brain that was somehow neurodevelopmentally divergent from what is “neurotypical” could have been “on track” for problem behavior without a TBI. We know, for example, that attention-deficit/hyperactivity disorder is associated with neurological dysfunction and is a risk factor for TBI; it also increases the chances of poorer outcomes after TBI.32,33 Thus, TBI may play a role, potentially not only as a key cause but also as an amplifier of socioaffective dysfunction.


Ryan and colleagues22 recently showed that adults who had had severe TBI as children were significantly poorer at emotion perception than controls; this was associated with reduced volume of the posterior corpus callosum, presence of frontal pathology, lower socioeconomic status, and less-intimate family environment. In this issue, Ryan and colleagues describe a longitudinal follow-up study of 55 young adults who had sustained a mild or moderate-severe TBI in childhood (mean age = 23.85 years; injury age: 1-12 years).4 They report that 15% of the participants with a history of TBI were rated as having “trouble with the law” compared with 7% of the normative sample of 447. Furthermore, a quarter of their follow-up group demonstrated clinical or subthreshold levels of externalizing behavior in young adulthood and that externalizing behavior was associated with poorer preinjury adaptive functioning and more frequent pragmatic communication difficulty.

One key area where such communication difficulties can occur with significant consequences is between a young person and those in authority. Wszalek and Turkstra5 provide a review of common language impairments in youth with TBI. They note how such problems typically occur consequent to the usual neurocognitive deficits of TBI. Both expression and comprehension are affected—from problems extracting the gist of speech and prose to “mind-reading” intentions of others. They describe how these communicative impairments may lead to problems for young offenders in encounters with officers of the justice system. They note how such legal devices as the Miranda Rights—which require police officers in the United States to warn a suspect of his or her rights (to remain silent, to have legal representation) before arrest—may not be understood by those with TBI, placing them at a pronounced disadvantage in dealing with the legal system. These authors also note that capacity to stand trial requires linguistic competence, which may be compromised for many with a history of TBI. They recommend a range of assessments that may help identify those who may be unable to follow legal proceedings. Wszalek and Turkstra also describe how social science research has already influenced judicial practice in certain areas—such as the abolishment of the death penalty in the United States for adolescent offenders and those with mental retardation. These recommendations are consistent with an important body of literature in the field of language and law (mainly in the United States) that addresses the issue of children's (in)ability to understand the basic meanings and nuances of language used throughout the adjudication process—by police and in court.34–36 Although none of these language and law studies deal specifically with TBI, these studies may dovetail with current work in the field of neuroscience and, indeed, offer an opportunity for genuine interdisciplinary efforts to improve engagement by—and promote fair treatment of—young offenders in the justice process.

Once young offenders with TBI have entered the justice system, it is likely they will remain within it or return. In a systematic review, Hughes and colleagues6 examined the prevalence of TBI among young people in custody compared with estimates within the general youth population. They reported on 10 studies, 4 of which included control groups. No studies examined comorbidity of TBI and other neurodevelopmental disorders. Prevalence of TBI among incarcerated youth ranged from 16.5% to 72.1%. Of particular note, they found that, where there were control groups or directly comparable studies within the general population, there was strong and consistent evidence of a higher prevalence of TBI among incarcerated youth, with this disparity being more pronounced as the severity of the injury increased.

In England, to begin to address the problem of TBI in young offenders, a new semistructured interview schedule—the Comprehensive Health Assessment Tool (CHAT)—has been developed.37 It is now mandatory for all young people coming into custody to be evaluated for mental health and neurodevelopmental disabilities—including TBI. Chitasabesan and colleagues7 describe a study in which 93 male participants aged 15 to 18 years were evaluated using a range of different neurocognitive and mental health measures including the Rivermead Post-Concussion Symptoms Questionnaire and the CHAT. The participants were consecutive admissions to a custodial secure facility. Eighty-two percent reported at least 1 TBI, and 44% were found to have ongoing neuropsychological symptoms. More than half had sustained multiple injuries. Eighteen percent of those reporting a TBI had moderate-severe postconcussion symptoms (primarily irritability, poor concentration, and impulsiveness). This group appeared to have a range of comorbid issues: 29% with attention-deficit/hyperactivity disorder; 36% had speech and language impairments; more than two-thirds had alcohol and cannabis misuse problems; and half were assessed as being at risk of deliberate self-harm or suicide. Chitasabesan and colleagues7 then describe a brain injury service developed by The Disabilities Trust Foundation to enable better assessment and rehabilitation of those with TBI in youth custody settings. The protocol was incorporated into a service pathway and is based on a successful model of interventions for adult offenders with TBI in an adult custodial secure facility.38


Sir Winston Spencer Churchill stated in the House of Commons on July 20, 1910:

The mood and temper of the public in regard to the treatment of crime and criminals is one of the most unfailing tests of the civilisation of any country ... [and there needs to be] a constant heart-searching by all charged with the duty of punishment, a desire and eagerness to rehabilitate in the world of industry all those who have paid their dues in the hard coinage of punishment, tireless efforts towards the discovery of curative and regenerating processes, and an unfaltering faith that there is a treasure, if you can only find it, in the heart of every man.39

In considering TBI in those who offend, what is revealed is that young people who had the least opportunity to thrive are the most likely to be injured and, in time, enter the justice system. It is often opined that if the rate of TBI is so high among those in custody, to meet their needs would overwhelm the system. The rates of TBI are high, but this does not mean that the situation cannot be at least partially remedied. There are opportunities to make reasonable progress in addressing TBI without overtaxing custodial systems. It should be possible to identify those who simply need some advice for managing effects of milder TBIs, as well as providing neurorehabilitation services to at least some portion of those whose injuries are more substantial.

Many benefits can accrue to the justice system by addressing TBI in young offenders. Indeed, should the authorities not act to identify those who have major ongoing problems due to TBI, the judicial and custodial systems will remain “in the dark”—not knowing what they need to know to decide in a wise and informed fashion. Furthermore, failure on the part of the authorities to address the needs of those with TBI actually causes greater chaos in the lives of those they are charged to manage them, as well as in society at large. For example, a young person in custody who cannot remember the rules to follow to gain privileges (or those rules to follow to avoid being denied privileges) and who becomes the victim of other inmates' goading and made to lose his or her temper could, instead of being told what to do and punished for not understanding, be taught how to change his or her behavior by using visual cues to “be calm” and “earn TV points.”

Let's be clear, then, about what can be gained from better management of TBI in relation to crime, youthful crime in particular. Crime has very high costs, both for society as a whole and from the narrower perspective of public finances. An indication of the orders of magnitude involved is given in a recent report by the UK National Audit Office (NAO) on the costs to the criminal justice system of a cohort of 83 000 young offenders40 who committed their first offence in 2000.41 The researchers analyzed their subsequent offending behavior for the period 2000-2009 and found that, on average, each young offender cost the criminal justice system £8000 ($12 400) a year and each of the 10% most serious offenders cost £29 000 ($45 000) a year. According to the UK Home Office (the department of government that oversees the police forces), costs to the criminal justice system account for about 20% of the total financial burden of crime, including costs to victims. Allowing for this, the overall costs of crime over the 10 years of the NAO study are around £400 000 ($622 000) per average young offender and around £1.45 million ($2.25 million) per the most costly 10%. These are enormous costs and imply that even if interventions are only moderately effective in reducing reoffending, they are still likely to be good value for money and so should be provided. It is clear from these analyses that, given the role of TBI in crime, a range of actions could be beneficial.

First, we need to take steps to prevent TBI in those most likely to incur such injuries and, indeed, prevent those who may have had a TBI from having further TBIs. There are various campaign programs and educational information sources regarding prevention.41–43

Messages regarding prevention may need to be geared to the age of the child. Barriers to educative approaches (such as potential parental fears of being seen as neglectful) need to be addressed. Preschool workers could target messages regarding risk and enabling a safe environment. There is also a role for those who plan and develop housing and recreational spaces regarding managing risks. In older groups, injuries are more likely in public. In sports, there need to be comprehensive systems to enable teachers and coaches to better manage TBI. In leisure time activities where alcohol and risk taking are involved, targeting of messages for reducing the risk of injury is needed, such as initiatives that target binge drinking.

Second, it is vital that young people with TBI are evaluated and enabled to return to school and social life safely and effectively. The nature and severity of the brain injury should be taken into account, as well as the “double hazard” factors, such as preinjury status and familial support. It is vital that social-behavioral consequences of TBI be addressed. Survivors of TBI need help for their “social brain” to navigate their way—to manage interactions with others so that they do not respond with anger and violence.

Third, screening for TBI and problems in communication needs to be available in justice systems. Such screening should happen at least at the individual's point of entry, and perhaps multiple times, but certainly in a way that informs subsequent proceedings. Brief screening could occur at arrest or at charging. Assessments would be vital at pretrial and presentencing—as such measures would ensure that young offenders can be engaged in the justice process and also help identify how forensic rehabilitation could be structured to enable behavior change. Assessments need to be easily conducted by professional and nonprofessional staff at the “coal face” to highlight when a TBI and/or sociocommunication problems are likely. Therefore, screening tools need to be developed for use, for example, by police and probation services. Appropriate provision of more detailed assessment by qualified practitioners should be provided when needed.

Fourth, screening and assessment for TBI within custodial systems are clearly important. Identification of TBI could increase understanding of factors that may lead to offending and increased likelihood of recidivism and assist in identifying relevant interventions such as psychoeducation and rehabilitation programs. We would argue that, for example, targeting social communicative dysfunction would be particularly important. We also believe that attempts to manage mood, drug use, and anger issues may be improved if therapies were designed to take account of the impact of TBI sequelae.

Fifth, we need comprehensive research that fully integrates theoretical models from forensic and clinical neuroscience domains to address TBI issues. Research should include structural neuroimaging (such as diffusion tensor imaging) to elucidate brain systems affected by TBI across severities, functional magnetic resonance imaging to examine for neurocognitive disorders linked to offending (such as in executive and socioaffective systems), longitudinal arms to studies to follow up offending—and nonoffending—patterns of behavior over time, and, of course, the effects of interventions.

Finally, there must be the political will to turn research findings into policy initiatives to drive changes in the management of youth who offend. There needs to be greater awareness at all levels of the justice system of the role of TBI in crime. Those who commission and pay for services for offenders ought to demand that providers (be they healthcare, forensic, etc) assess and manage TBI in offender populations. Moreover, those who regulate services—the “watchdogs” as it were—need to be vigilant for TBI as an important issue—one that affects access to justice and requires appropriate care and rehabilitation—so that they hold governments to account for delivery of humane services. These are roles in the United Kingdom, for example, that Children's Commissioners and Her Majesty' Inspectorate of Prisons undertake.44,45 Through such integration of research, policy, and clinical practice and through service design and delivery, we may reduce the chances of lives being lost and blighted by crime.

—W. Huw Williams, PhD

Issue Editor

School of Psychology, University of Exeter

Exeter, Devon, United Kingdom

Karen A. McAuliffe, PhD

School of Law, University of Exeter

Exeter, Devon, United Kingdom

Miriam H. Cohen, MSc

Institute of Neurology University

College, London, United Kingdom

Michael Parsonage, MA

Centre for Mental Health, London

United Kingdom

General The Lord David

John Ramsbotham, GCB, CBE, MA

House of Lords, Westminster, London

United Kingdom


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