After Richard Hodges pleaded guilty to cocaine possession and residential burglary, he appeared somewhat dazed and kept asking questions that had nothing to do with the plea process. That’s when the judge ordered that Hodges undergo a neuropsychological examination and magnetic resonance imaging (MRI) testing. Yet no irregularities turned up.
Hodges, experts concluded, was faking it. His guilty plea would stand.
But experts looking back at the 2007 case now say Hodges was part of a burgeoning trend: Criminal defense strategies are increasingly relying on neurological evidence—psychological evaluations, behavioral tests or brain scans—to potentially mitigate punishment. Defendants may cite earlier head traumas or brain disorders as underlying reasons for their behavior, hoping this will be factored into a court’s decisions. Such defenses have been employed for decades, mostly in death penalty cases. But as science has evolved in recent years, the practice has become more common in criminal cases ranging from drug offenses to robberies.
“The number of cases in which people try to introduce neurotechnological evidence in the trial or sentencing phase has gone up by leaps and bounds,” says Joshua Sanes, director of the Center for Brain Science at Harvard University. But such attempts may be outpacing the scientific evidence behind the technology, he adds.
“In 2012 alone over 250 judicial opinions—more than double the number in 2007—cited defendants arguing in some form or another that their ‘brains made them do it,’” according to an analysis by Nita Farahany, a law professor and director of Duke University’s Initiative for Science and Society. More recently, she says, that number has climbed to around 420 each year.
Even when lawyers do not bring neuroscience into the courtroom, this shift can still affect a case: Some defendants are now using the omission of neuroscience as grounds for questioning the competency of the defenses they received. In a bid to untangle the issue, Sanes, Farahany and other members of a committee of The National Academies of Sciences, Engineering and Medicine are meeting in Washington, D.C., on Tuesday to discuss what they have dubbed “neuroforensics.”
“The meeting is largely future-oriented, and focused not so much on law enforcement use, but on admissibility in court,” Steven Hyman, co-chair of the committee and director of the Stanley Center for Psychiatric Research at the Broad Institute, wrote in an e-mail to Scientific American. The gathering will likely dive into a variety of questions about how neuroscience and genetics should be used in the courtroom—including how brain scans indicating the presence of pain should be used in assessing disability benefits, and when someone’s biology can explain behavior. Another controversial discussion point will be recent proof-of-concept work on how pictures of what’s happening in the brain—functional magnetic resonance imaging (fMRI) or an EEG test (which captures electrical brain activity)—could be coupled with computer algorithms to eventually reconstruct what a person saw or to capture other aspects of human perception.
The committee will also be talking about the role of genetics in the courtroom—a trend that may be declining, even as neuroscience takes a more prominent role in criminal cases. In 2013 there were 18 cases in which judicial opinions mentioned genetics; in 2014 there were only 10 and in 2015 the number dropped to seven, according to an unpublished review by Farahany. “There may have been more attempts than this that simply aren’t discussed [in judicial decisions], but if they have relevance to the outcome in the case, then they would have been discussed,” she says. Farahany believes the drop is due to the fact that science linking certain genetic mutations with criminal tendencies has simply not panned out, even as scientists continue to uncover more detail about how our brains influence our behavior.
Currently, most neuroscience enters the courtroom in the form of psychological evaluations or behavioral studies. Actual snapshots of the brain from MRIs or CT scans are only showing up in about 15 percent of judicial opinions that involve neuroscience, according to Farahany’s research. But ahead of their meeting, committee members cautioned the role of brain scans could surge in the very near future—a good reason to start discussing these issues now.
“This is such a fraught area, and it’s prone to hype and overstatement,” Sanes says of neuroforensics. But at the meeting, “hopefully we’ll both get some feedback about good avenues to explore, and get some suggestions about how to mount a full study, he says. “This meeting is the starting point.”