Brain trials

A reader sent me this article from a legal publication regarding the use of neuroscience evidence in the courtroom. I've discussed before about how the diagnosis of psychopath is often used in parole hearings as an argument against granting the prisoner parole (see also this NPR article about a prisoner named Robert Dixon). This article was a fun read because it uses stories that illustrate the difficulties well:


Take the case of a 40-year-old married schoolteacher from Virginia who during the year 2000 inexplicably began to have a sexual interest in children. He surreptitiously collected and viewed child porn on the Internet and was convicted of trying to molest his stepdaughter. The night before sentencing, he complained of horrible headaches. At the hospital he talked of suicide, made sexual advances to staff, spoke of raping his landlady and urinated on himself.

An MRI revealed that the teacher had a large orbitofrontal tumor, a growth on an area of his brain associated with social behavior. After surgeons removed the tumor, he was no longer considered a threat and completed a sexual rehab program. But a year later, he began getting headaches and once again collected pornography. Another MRI showed the tumor had regrown, and it was removed again.

Dr. Russell Swerdlow, a neurologist who treated the teacher at the hospital and later wrote about the case in the Archives of Neurology, says that such radical behavioral changes are not surprising. “But it was the first case in which the bad behavior was pedophilia,” says Swerdlow, a neuro-scientist and professor at the University of Kansas. “What was so striking about this was his inability to act on his knowledge of what was right or wrong.”

Swerdlow says when pathways are broken between the orbitofrontal lobe and the amygdala, a part of the brain involved in emotional responses and decision-making, the result can be impulsive behavior. “You don’t get the feedback that controls your decisions. You don’t have the brakes on your behavior,” he says.

Morse says that while the teacher may deserve some mitigation in sentencing because of his ailment, it’s not clear whether he lacked the ability to control his impulses, or simply chose not to. “People want to say his tumor made him do it. He made him do it. There is always a reason people do it,” Morse says. “We don’t give a pass to the other pedophiles. He felt an urge, which he understood and did not resist, but acted on it.”

While it’s true that not everyone who suffers brain damage commits criminal acts, there are plenty of anecdotal cases in medical literature showing that it causes behavioral changes, including impulsiveness, depression, aggression, inappropriate sexual behavior, lack of thought control and violence among people who prior to their injuries did not exhibit such behaviors. But how that should be considered in criminal culpability—and what science can truly explain—remains murky.

I love this story because when you start reading it you think, this poor guy. He's not the one making the decisions, it's his broken brain. Then you get to the part about how we don't give a pass to the other pedophiles and then it becomes clear that this issue is thornier than most people have considered. For instance, lucky you (most of you) to have not been born with a sexual lust for children. But just wait until you get some crazy brain tumor! Then you are truly up Shit Creek.