brain-scanYou’ve been convicted of a violent crime. You walk into the courtroom for sentencing and see a scan of your brain projected on the big screen. A neuroscientist is on the stand circling an area of the scan with her laser pointer.

“You can see here,” she says, “that the defendant is 100% likely to commit another act of violence.”

Because of her statement, the Judge gives you life, or worse, the death sentence.

Currently, the courtroom might use brain imaging evidence to support some set of facts, like to suggest a defendant’s innocence or to boost a claim of insanity. Brain activity and structure aren’t yet used to assess a defendant’s risk of re-offense or assign a sentence.

But neuroscientists are working toward just that.

Researchers suggest that brain imaging technology can improve risk assessments, helping courts more accurately decide whether a person should be given a few years or locked up for life.

Are Judges likely to apply the “neuroprediction” method any time soon?

How Courts Assess Risk of Re-Offense

Judges are always worried about the headline consequences of releasing a dangerous guy prematurely but there is also the problem of holding a harmless, low-risk person behind bars for decades. Both are unfair and unjust.

In the old days, judges used their own instincts to decide sentencing, weighing information from police reports, criminal histories, and questioning to figure out how likely a defendant was to re-offend.

Eventually, the courts started using psychiatrists’ evaluations or risk assessment algorithms in the hopes of coming up with more accurate predictions. These algorithms analyze data from thousands of similar defendants to determine whether a person is statistically more likely to repeat his or her crime.

Risk assessment algorithms compare all kinds of information on the defendant and similar defendants, including:

  • Age
  • Citizenship
  • Current charge
  • Education
  • Employment history
  • Failures to appear
  • Gang association
  • History of arrests and convictions
  • Length of residence
  • Marital status
  • Mental health
  • Outstanding warrants
  • Parents’ criminal history
  • Pending charges
  • Phone coverage
  • Previous incarcerations
  • Probation and parole status
  • Substance abuse

Some courts use these, some don’t. Some argue that risk assessment algorithms work, while others say they still have a high degree of racial bias.

Though Hispanics and African Americans make up around 32% of the US population, they made up 56% of all incarcerated people in 2015 according to the NAACP. Using the risk assessment algorithm, minorities are going to get harsher sentences because they’re arrested and incarcerated more frequently than other segments of society. The algorithm inherently works against them.

Will Brain Scans Eliminate Courtroom False Positives and Racial Bias?

Since today’s risk assessment algorithms are limited by their potential for false positives and racial bias, neuroscientists are proposing a new risk assessment method – analyzing the brain. Researchers at the University of New Mexico say that brain activity and structure may be a better estimate of a person’s risk of re-offense.

As we saw above, risk assessments use age to help predict future criminal activity. Statistically, defendants that are 18-25 years old are most likely to engage in risky behavior.

University of New Mexico researcher Kent Kiehl feels that “brain age” might be a better predictor than chronological age. According to Kiehl, brain age is a measure of the brain’s gray matter – areas of the brain involved in emotions, memory, speech, self-control, and decision-making.

In a recent study, Kiehl’s team examined whether “brain age” could predict re-arrest. Researchers analyzed 1,332 brain scans of males in juvenile or prison facilities age 12 to 65. They found that they could predict re-arrest by combining measures of brain activity and brain age with measures of substance abuse and certain psychopathic traits like impulsivity and irresponsibility.

Researchers also suggest that abnormalities in areas of the brain responsible for emotional processing and moral decision-making could contribute to criminal activity. Earlier research by the same group showed that low brain activity in the area of the brain that controls inhibition was a more accurate predictor of re-arrest than factors used in risk assessments.

Kiehl says that “brain imaging can’t tell you with 100 percent accuracy what an offender will do,” adding, “neither can a pen-and-paper risk assessment.”

Of course, scientists also tried to institute lie detectors into courtrooms. And, though they are applied as an interrogation tool, they still aren’t admissible as evidence in a court proceeding. There are too many false positives. Heavy reliance on such tests could easily free a guilty defendant or convict an innocent one.

Even suggesting “scientific evidence” of guilt can be incredibly dangerous when presented to an untrained judge or jury who may accept the data as accurate and reliable on face value. A brain scan all lit up on the screen is impressive. The untrained eye isn’t going to ask how it works or whether it’s scientifically sound. They’re likely just to believe it.

Some things can’t yet replace the intuition and intellect of the human mind. For now, a Judge and jury’s interpretation of the case before them is still the safest means of determining how a defendant should be treated upon conviction.