The misapplication of neuroscience with regard to juvenile crime

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On Aug. 1, 1966, Charles Whitman became the first school mass shooter in American history. From the tower of the University of Texas in Austin, he shot 47 people, 16 fatally. Whitman died in a shootout with the police. An autopsy showed that he had a small brain tumor. It pressed against his amygdala, which is critical in controlling fear, anger and aggression. Did his brain tumor make him so violent that he couldn't help committing the heinous crime? No one has the answer.

On Nov. 8, 2022, two teen brothers, 15 and 17, gunned down Zaria McKeever in her apartment in Brooklyn Park. Erick Haynes, McKeever's ex-boyfriend, is accused of supplying the teens with the weapon and orchestrating the killing. This case has brought neuroscience into the legal debate. With their brains still years from reaching full adulthood, should the two teenagers be held accountable like adults?

A teenager's brain is still developing. The part of the brain inside the forehead is called the frontal cortex. This brain structure doesn't fully mature until the age of 25. It has many functions, including impulse control. Without impulse control, you may run a red light in a hurry, buy a fancy car outside your budget or punch someone with a different viewpoint. Some patients who suffer from severe frontal cortex damage become highly impulsive. But only a small number of them exhibit uncontrollable aggression.

Former New England Patriots player Aaron Hernandez was 23 when prosecutors charged him with the murder of his friend Odin Lloyd. Hernandez planned the killing, drove Lloyd to a remote location and shot him multiple times. The jury convicted him. The judge sentenced him to life. Hernandez later hung himself in jail. An autopsy showed that he had substantial brain damage. Did the injury to his maturing brain cause his violent behavior? Few neuroscientists can make that claim with confidence.

The frontal cortex is like a car's brake. Does a well-functioning brake guarantee no accidents? No, especially on Minnesota's icy roads in the winter. Similarly, a fully matured frontal cortex doesn't assure total control of one's actions. Alcohol impairs this brain structure, turning a 40-year-old drunk into a rowdy teenager. If alcohol is the cause of a car accident, the drunken driver is accountable, not Mr. Jack Daniels.

What if the frontal cortex is not completely mature, like in teens? When it comes to the brain, immaturity doesn't equal impairment. Most teenagers can abide by laws and follow social norms. The ability to rein in impulses grows stronger and faster as the frontal cortex marches toward adulthood. We can tamp down our juvenile behavior way before turning 25. It is misleading to insist that a teenager's underdeveloped brain causes the pulling of a trigger.

Driving a new car is not a predictor of road safety. Neither is driving a jalopy with a half-worn brake. When an accident happens, there are many factors to examine. A faulty brake may be one. When someone commits a crime, there are many reasons. We don't know enough about the brain to draw a sound conclusion between age and criminal behavior.

Hennepin County Attorney Mary Moriarty refused to try the teen brothers as adults. Her reason is that the brain doesn't develop enough to control impulsivity until age 25. If her argument stands, the main perpetrator of the crime, Erick Haynes, who is 22, should be tried as a juvenile. Aaron Hernandez was 23 when he fired the fatal shots. Let's not forget that Dzhokhar Tsarnaev was only 20 when he set off a bomb at the 2013 Boston Marathon. He has been appealing his death sentence.

Today, you can justify any decision by spitting out a few sound bites with "brain" or "neuroscience." But in reality, there is hardly any consensus among neuroscientists. Making decisions based on misunderstood neuroscience doesn't do justice.

Reasoning by citing neuroscience seems like a trend. However, we learn from neuroscience that if someone is never reasoned into a decision, it is impossible to reason the person out of that decision.

Terry Wu, of Plymouth, is a neuroscientist, public speaker and consultant.