The Cautionary Instruction: Brain development becomes courtroom staple

Friday, 29 November 2013 06:00 AM Written by  Matt Mangino

201311129 brain photocom149148235 150The U.S. Supreme Court has helped spur a bevy of action focusing on the effect of adolescent brain development on criminal activity.

Starting with Roper v. Simmons, a 2005 case that abolished the death penalty for juveniles, and continued with Graham v. Florida, a 2010 decision finding juvenile offenders could not be sentenced to mandatory life-without-parole for non-homicide offenses and most recently in Miller v. Alabama, where the Court found that a state cannot impose a life-without-parole sentence for juvenile homicide offenders on a mandatory basis.   

Roper cited behavioral studies, while Graham and Miller cited adolescent brain research suggesting that juveniles may be less culpable than adults.

Dr. Jay Giedd of the National Institute of Mental Health says brain scans show that the frontal lobes do not fully mature until age 25, and their connections to other parts of the brain continue to improve to at least that age.

Research suggests that this circuitry weighs how much priority to give incoming messages like "Do this now" versus "Wait! What about the consequences?" In short, the frontal lobes play a key role in making good decisions and controlling impulses.

The inexplicable behavior and poor judgment teens are known for almost always happen when teens are feeling high emotion or intense peer pressure, conditions that overwhelm the still-maturing circuitry in the front part of brain, Giedd explained.

Judges and juries are being swayed by studies showing that adolescent brains do not function the same as adult brains. One study by Kristina Caudle, a neuroscientist at Weill Cornell Medical College used a technology called functional MRI to observe how the brains of people from 6 to 29 reacted to a threat.

"The typical response — and what you might think is a logical response — is to become less impulsive, to sort of withdraw, to not act when there is threat in the environment," Caudle says. "But what we saw was that adolescents uniquely seemed to be more likely to act. So their performance on this task became more impulsive."

“The idea is, because of their immature brains, adolescents may be more likely to engage in reckless and sensation-seeking behavior—and to get involved in criminal activity,” explained Columbia Law School Professor Elizabeth S. Scott.

"Teenagers tend to be drawn to danger,” BJ Casey of Sackler Institute for Developmental Psychobiology at the Weill Cornell Medical College told Popular Science. “It’s as if they [juveniles] can’t help themselves.” That is not to say they cannot be trusted to make any decisions whatsoever, just that those abilities “might be compromised in emotional setting.”

Though teenagers might be at the healthiest and quickest stage of their life, Casey said, “in the heat of the moment, they falter. We don’t tend to do that as much as adults.”

(Image: Jana Blašková/Getty Images)

Matthew T. Mangino is of counsel with Luxenberg, Garbett, Kelly & George, P.C. He is the former district attorney of Lawrence County and just completed a six year term on the Pennsylvania Board of Probation and Parole. His weekly column on crime and punishment is syndicated by GateHouse New Service. You can read his musings on the criminal justice system at and follow Matt on Twitter @MatthewTMangino.

Join the conversation:

To report inappropriate comments, abuse and/or repeat offenders, please send an email to and include a link to the article and a copy of the comment. Your report will be reviewed in a timely manner. Thank you.