Letter

• neurodevelopmental disorders
• intellectual disability
• autism spectrum disorder
• forensic psychiatry
• criminality
• violence

Editor:

I read with interest the article by Guina and colleagues¹ on neurodevelopmental disorders (NDs) and criminal responsibility. Although the authors deserve credit for drawing attention to this intersection, I have two concerns regarding their framing of insanity and their reliance on dated violence-risk statistics.

First, the article emphasizes not guilty by reason of insanity (NGRI) as the primary legal frame for considering NDs. In capital and serious violent crime contexts, however, the critical role of ND evidence is rarely in establishing insanity. Instead, it is in mitigation, particularly following Atkins v. Virginia,² Hall v. Florida,³ and the developmental reasoning that influenced Roper v. Simmons.⁴ These cases recognize that intellectual disability and developmental immaturity constrain culpability, regardless of an “insanity” determination. Conflating neurodevelopmental impairment with insanity, whether in the legal, clinical, or colloquial sense, perpetuates the misconception that only those deemed “insane” warrant protection. In reality, the brain of an alleged capital murderer is, by functional definition, abnormal. But this abnormality may fall short of any qualitative diagnostic label while still remaining highly relevant to sentencing and proportionality.

Secondly, Guina et al.¹ cite early 1990s work suggesting that men with intellectual disability (ID) are five times, and women 25 times, more likely to commit violent crime than counterparts without ID. These figures are misleading when presented without context. More recent large-scale registry studies from the United Kingdom,^5,6 Denmark,⁷ Sweden,^8,–,10 and Australia^11,12 show far lower relative risks, often attenuating entirely once comorbid psychiatric illness, trauma history, and socioeconomic adversity are considered. Today, the consensus is that intellectual disability and autism spectrum disorder, in the absence of such comorbidities, do not independently predict violent or sexual offending and, in some analyses, may even be protective.^2,–,4 Repeating inflated risk estimates from small, outdated cohorts risks stigmatizing individuals with NDs and misinforming courts and the public.

In nearly every capital case I have reviewed, neurodevelopmental evidence has been salient in psychosocial histories as well as structural and functional neuroimaging, not because defendants meet criteria for legal insanity, but because immaturity,¹³ intellectual deficits, or trauma-related dysfunction bear directly on culpability. Forensic psychiatry’s responsibility is to make these distinctions clear: neurodevelopmental impairment matters, but it is not synonymous with insanity. Likewise, risk assessment must be grounded in current evidence, acknowledging the mediating roles of comorbidity and context.

Clarifying distinctions between neurodevelopment and insanity and presenting modern, nuanced risk data will improve the accuracy of psychiatric testimony, strengthen credibility in legal settings, and reduce stigma by better aligning science, law, and public understanding. We need not wait for a more objective and comprehensive diagnostic framework in psychiatry before initiating these changes within our expert work.

• © 2025 American Academy of Psychiatry and the Law