Neuroscience in court: My brain made me do it
By Kate Kelland
IS "MY BRAIN MADE ME DO IT" A DEFENCE?
And when it comes to prison, should pedophiles, psychopaths and other violent criminals be punished less severely if their behaviour can be blamed on biology? Is "my brain made me do it" a defence that warrants recognition with lighter sentences, or even no jail time at all?
"(It) raises the whole issue of what you think sentencing is for," says Blakemore. "Is it about punishment? Is it about retribution? Is it about remediation and rehabilitation? Is it about protecting society? Well, to some extent it's about all of those things."
Recent evidence - from both real and hypothetical cases - suggests judges are sympathetic to neurobiological evidence as mitigation.
A study published in the journal Science this month showed that criminal psychopaths in the United States whose lawyers provide biological evidence for their brain condition are more likely to be sentenced to shorter jail terms than those who are simply said to be psychopaths.
For the study, researchers at the University of Utah tweaked the real-life case of Stephen Mobley, a 39-year-old American who was sentenced to death in 1994 after robbing a Domino's pizza place in Georgia and shooting dead the restaurant's manager.
At his trial, Mobley's lawyer presented evidence in mitigation showing the accused had a variant of a gene called MAO-A that has been dubbed the "warrior" gene after scientists found it was linked to violent behaviour.
In the Science study, judges were given a hypothetical case loosely based on Mobley's, where the crime was a savage beating with a gun, rather than a fatal shooting.
All the judges were told the defendant was a psychopath, but only half were given expert testimony on the genetic and neurobiological causes of his psychopathy. Those who got the neuroscientific evidence were more likely to give a shorter sentence - generally about a year less, the study found.
Pietrini worked on a similar real-life case in Italy in 2009 - thought to be one of the first criminal cases in Europe to use this type of neuroscientific evidence.
It involved Abdelmalek Bayout, an Algerian living in Italy, who was tried and convicted for fatally stabbing a man who teased him in the street.
After conducting a series of tests on the Algerian, Pietrini and colleagues said they had found abnormalities in imaging scans of his brain, and in five genes that have been linked to violent behaviour - including MAO-A.
A 2002 study led by researchers at the Institute of Psychiatry at King's College London linked low levels of MAO-A with aggressiveness and criminal behaviour in boys who were raised in abusive environments.
Bayout's lawyers got his sentence reduced by arguing that this and other bad genes had affected his brain and were partly to blame for the attack.