Mental Health and Neurodevelopmental Disorders, Criminality, and Criminal Responsibility
Explore the connection between mental health and neurodevelopmental disorders, criminality, and criminal responsibility.
It is now settled science that youth like Carly deserve special sentencing protections.
This is based on the fundamental fact that adolescents are developmentally different from adults in ways that deeply affect their judgment, impulse control, and vulnerability to external pressures. Neuroscientific research shows that around the ages of 14 to 15, the part of the brain that regulates emotional intensity—the amygdala and related limbic structures—reaches peak reactivity. At the same time, the prefrontal cortex, responsible for rational thinking, risk assessment, and long-term planning, is still underdeveloped and continues maturing well into a person’s mid-20s.
As a result, everything feels more intense and overwhelming at that age—emotionally, socially, and psychologically. This immaturity isn't just about bad decisions; it's about an underdeveloped ability to weigh consequences, resist peer pressure, or self-regulate in moments of distress. These are biological facts, not character flaws.
The U.S. Supreme Court has recognized this reality in key rulings like Roper v. Simmons (2005), Graham v. Florida (2010), and Miller v. Alabama (2012), emphasizing that "children are constitutionally different from adults for purposes of sentencing."
Cases like Carly’s demand this understanding. Sentencing a young teenager to life without parole ignores decades of research and runs counter to both constitutional values and common human decency.
Neuroscientific research shows that around the ages of 14 to 15, the part of the brain that regulates emotional intensity—the amygdala and related limbic structures—reaches peak reactivity. At the same time, the prefrontal cortex, responsible for rational thinking, risk assessment, and long-term planning, is still underdeveloped.
James Garbarino
Professor Emeritus
Education
Ph.D., Cornell University
My research focuses on issues in the social ecology of child and adolescent development. I have a long standing interest in a wide range of violence-related issues - war, child maltreatment, childhood aggression, and juvenile delinquency. In 1991 I undertook missions for UNICEF to assess the impact of the Gulf War upon children in Kuwait and Iraq, and have served as a consultant for programs serving Vietnamese, Bosnian and Croatian children. I also serve as a scientific expert witness in criminal and civil cases involving issues of trauma, violence, and children. In all these issues I am concerned with how developmental processes are shaped by the human ecology in which they occur, and have a particular interest in matters of spirituality and identity in this process. After completing a project on physical aggression in girls (resulting in a book entitled See Jane Hit: Why Girls Are Growing More Violent and What We Can Do About It), I am currently working on a project dealing with childhood in the face of the terrorist threat.
Publications/Research Listings
Garbarino, J. and DeLara, E. (2002) And Words Can Hurt Forever: How to Protect Adolescents from Bullying, Harassment, and Emotional Violence (NY: Free Press, 2002
Garbarino, J. and Bedard, C. (2001) Parents Under Siege: Why You Are the Solution, Not the Problem, in Your Child's Life. NY: Free Press.
Garbarino, J. (1999) Lost Boys: Why Our Sons Turn Violent and How We Can Save Them. (NY: Free Press).
Garbarino, J. (1995) Raising Children in a Socially Toxic Environment (1995). San Francisco: Jossey-Bass Publishers.
Understanding Neurodevelopmental Disorders
Neurodevelopmental disorders (NDDs) encompass a range of conditions that affect the development of the nervous system. Individuals with NDDs may face challenges in communication, social interaction, and behavior. It is crucial to consider the impact of NDDs on an individual's actions and criminal responsibility.
Addressing Criminality and Mental Health
The intersection of criminality and mental health is complex. Many individuals with mental health issues may come into contact with the criminal justice system. It is essential to provide support services and advocate for fair treatment for individuals with mental health concerns.
Implications for Criminal Responsibility
Courts must take into account the influence of mental health and neurodevelopmental disorders when determining criminal responsibility. Failure to consider these factors can lead to unjust outcomes. It is crucial to raise awareness and educate the community about the impact of these conditions on criminal behavior.
Unfair Sentencing of Juveniles with Mental Illness: A Crisis We Ignore.
Every year, young people with serious mental health conditions are sentenced as if they were fully rational adults—with no real regard for their diagnoses, trauma, or developmental stage.
Courts must take into account the influence of mental health and neurodevelopmental disorders when determining criminal responsibility. Failure to consider these factors can lead to unjust outcomes. It is crucial to raise awareness and educate the community about the impact of these conditions on criminal behavior.
➡️ A life sentence doesn’t solve the problem.
➡️ Ignoring mental illness only ensures the cycle continues.
➡️ Justice without mental health awareness is not Justice.
🧩 We need:
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Develop-informed-sentencing
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Access to psychiatric evaluations before trial
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Trauma-informed courtrooms
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Treatment options—not just prison
The USA legal system still relies on outdated standards
like the 19th-century “M'Naghten Rule”
It only asks: “Did they know it was wrong?” That’s it.
As if brain trauma, memory blackouts, hallucinations, trauma, and dissociation don’t exist.
Carly was a teen with documented psychiatric struggles. Her mind was in crisis. Instead of treatment, she got a life sentence.
Mental illness and legal responsibility can coexist—but they must be understood together.
It’s time to stop throwing people away because their suffering makes us uncomfortable.
The M'Naghten rule was created in
1843
The M'Naghten rule is a legal test defining the defence of insanity that was formulated by the House of Lords in 1843
It is the established standard in UK criminal law and versions have been adopted in some US States. Its original wording is a proposed jury instruction:
Daniel M'Naghten c. 1856
"Every man is to be presumed to be sane, and ... that to establish a defence on the ground of insanity, it must be clearly proved that, at the time of the committing of the act, the party accused was labouring under such a defect of reason, from disease of the mind, as not to know the nature and quality of the act he was doing; or if he did know it, that he did not know he was doing what was wrong.
There are several studies showing that a successful insanity defense occurs in less than 1 percent of all criminal prosecutions,” said Jeffrey Metzner, M.D., immediate past president of the American Academy of Psychiatry and Law (AAPL) and chair of APA’s Council on Psychiatry and the Law.
🧩 We need:
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Proper mental health evaluations in juvenile courts
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Judges and juries trained to understand trauma and neurodevelopmental disorders
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Compassion without losing sight of accountability
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Laws that reflect modern science—not Victorian-era rules.
What happened to Carly is not just her tragedy.
We should all be asking: How many more young lives will we lock away instead of trying to heal?
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In Mississippi, the insanity defense is rarely successful. While defendants are presumed sane, if a reasonable doubt of sanity is raised, the prosecution must prove sanity beyond a reasonable doubt. Juries determine sanity, but acquittals based on insanity are rare.
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Mississippi faces significant challenges related to mental health, including high rates of mental health conditions and a strong stigma surrounding mental illness. This stigma, lack of awareness, and limited access to care continue to be major barriers to mental health support in the state.
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A significant percentage of adults in Mississippi report symptoms of anxiety and/or depressive disorders, often exceeding national averages.
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Many Mississippians hesitate to seek help for mental health concerns due to the stigma surrounding mental illness and a lack of understanding about it.
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People struggle with mental health every day, but location can matter in terms of treatment options and other mental health services.
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A study from Soliant analyzed the best and worst states for mental health by evaluating data from the Centers for Disease Control and Prevention and the U.S. Bureau of Labor Statistics.
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The study scored each state by measuring factors that impact mental health including unemployment rate, participation in physical activity, disconnected youth rate, access to healthy foods and the frequency of "poor mental health days" reported by the population.
