Posted on behalf of Emiliano Feresin.
For the second time in two years neuroscience and behavioral genetics have entered the Italian courts. Judge Luisa Lo Gatto of Como, near Milan, reduced the sentence of a convicted murderer from life to 20 years, after ruling that neuroimaging and genetic tests proved the partial mental illness of the defendant.
Stefania Albertani pled guilty in 2009 to having killed her sister, burned her corpse and attempted to kill her parents.
In 2009 another judge partially agreed that a murderer was mentally ill on the basis of abnormalities in brain-imaging scans and in genes linked to violent behaviour- including the so-called “warrior gene” MAOA (see ‘Lighter sentence for murderer with ‘bad genes’’).
The scientists involved in that case, Pietro Pietrini, a molecular geneticist and psychiatrist at Italy’s University of Pisa, and Giuseppe Sartori, a cognitive neuroscientist at the University of Padova, were brought in by Albertani’s defence team after two psychiatric reports reached opposite conclusions on her mental state. They performed a battery of psychiatric analysis together with Voxel based morphometry, an imaging technique for assessing structural changes in the brain, and genetic tests, which, they say, all show that Albertani is not in full possession of her faculties.
Albertani’s grey matter volume in the imaging scans is different from that of a control group – 10 healthy women – in the Anterior Cingulate Gyrus and insula areas, among others. Changes in the Anterior Cingulate Gyrus have been linked to reduced inhibition and to the processes that regulate truth-telling; insula changes have been linked with aggressive behaviour. “These alterations have to be considered in causal relation with the psychiatric syntomatology of the murderer,” Pietrini and Sartori concluded in their report. The genetic tests show that Albertani has low MAOA gene activity, which has been linked to violent behaviour.
But others are not convinced. “There is no one-to-one relation between a certain brain area and a certain psychological process, and structural findings on aggression are very unspecific,” says Stephan Schleim, a cognitive scientist at the University of Groningen, in the Netherlands. He adds that “studies have shown that low and high MAOA activity can overlap in the brain, hence identifying the gene alone does not determine MAOA activity in an individual brain”.
Advanced imaging techniques, such as functional magnetic resonance imaging, recently made their debut as forensic evidence in the US (see ‘Science in court: Head case’). But “despite many advances in the neuroscience of mental disorder and other psychological issues, for the law’s purposes, so far they add little to the behavioral analysis”, says Stephen Morse, professor of law and psychology at the University of Pennsylvania in Philadelphia. Morse emphasizes that the more complicated cases, such as the Albertani one, are those where neuroscience is less informative. Morse notes that the forthcoming revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), will not include neuroscientific diagnostic criteria.
Pietrini is convinced of the opposite: “neuroscientific means can already help in assessing mental illness and can be used in forensic science to help reduce subjective variability, without leading us to determinism”, he says.
See also – Nature’s special ‘Science in court’