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Brain injuries over-represented in justice system victims and perpetrators

30 January 2020

The Chief Science Advisor to the Justice Sector, Ian Lambie, has released a report, What were they thinking? A discussion paper on brain and behaviour in relation to the justice system in New Zealand.

The report, which is endorsed by the Office of the Prime Minister's Chief Science Advisor on behalf of the Forum of Chief Science Advisors, says there is a strong evidence base that throughout the criminal justice system that those suffering brain injuries are over-represented as both victims and perpetrators.

Dr Lambie's report says traumatic brain injury (TBI) rates are at least four times higher in justice-involved men than non-offending peers. More than one-third have had multiple, severe TBIs before the age of 15 (40% by assault and 20% in motor vehicle accidents). Almost all women in a New Zealand prison study had a history of multiple TBIs.

It says Canadian research showed that young people with fetal alcohol spectrum disorder (FASD) were 19 times more likely to be incarcerated than those without. Comprehensive assessments of 10 to 18-year-olds in Australian youth detention found that 36% had FASD - all undetected before the research. "New Zealand research is needed", the report notes.

New Zealand youth justice residents (aged 14 to 17 years) were seven times more likely than matched controls to have hearing loss in one or both ears. In language tests, 64% met criteria for language impairment, compared to only 10% of controls.

The report says screening on 120 people in New Zealand prisons by a literacy expert found that nearly half had significant dyslexia (52% of men, 43% of women) - previously undiagnosed. Over 80% had been at secondary school for two years or less, with many having been excluded in their first year.

"International research estimates that up to two-thirds of young offenders and 50% of adults in prison would have screened positively for ADHD in childhood. ADHD can make it hard to attend to relevant cues, remember all question parts and reply choices, provide coherent and accurate answers, and inhibit frequent “don’t know” responses, culpable statements or false information/confessions."

There is some evidence, the report says, that caregiver violence, sexual predation or intimate partner violence may be less likely to be reported to authorities where the adult victim has intellectual disability. People with intellectual disability have an estimated three to seven times greater risk of being victims of crime than people without it, especially sexual victimisation.

Dr Lambie says autism spectrum disorder (ASD) in the justice system is poorly researched. He says some ASD features may put people at risk of having difficulties, whether as victims or offenders, through different social behaviour or intense/repetitive interests/actions.

He says brain and behaviour issues need evidence-based solutions, not political ones. "Resources are overwhelmingly directed to prisons, rather than to cost-effective health, education and family support that would prevent people ending up there. Imagining that “criminals” with permanent brain damage will 'learn their lesson' in prison does not reflect current evidence or common sense."

"Difficulties with communication, some caused by a high degree of undetected impairment, disproportionately affect those involved in the criminal-justice system, and compound the issues that precede and precipitate their entry into that system. New Zealand researchers point out the sobering reality that we have a justice system designed for those with good verbal communication skills, and yet the majority of offenders lack exactly such skills, to the extent that their basic rights and access to justice may be being denied

"I think we can do better. Here is what a defendant with neurodisability said about appearing in court. Is this good justice? - 'I couldn't really hear, I couldn't understand, but I said 'Yes', whatever to anything, because if I say 'I don't know', they look at me as if I'm thick."

Last updated on the 30th January 2020