An American schoolteacher was found guilty of making sexual advances to his young stepdaughter. But on the day before he was to be sentenced he complained that he was losing his balance. He was discovered to have a large tumour pressing on his orbitofrontal cortex, a brain area regulating social behaviour and impulse control. Removal of the tumour brought about a return of his personality to his previous, normal behaviour. Some time later his inappropriate behaviour returned. It was discovered that his tumour had re-grown and, once again, removal returned his behaviour to normal. The drama of this near miscarriage of justice demonstrates how the brain may overcome the freedom of the will, and what effect this might have on the legal process.
Understandably, this has caused a flurry of action and investigation into the issue. The questions raised are of great importance and it is clear that, although some tentative answers can be made, both neuroscience and the legal system have a long way to go. Those with a professional interest may look up the comprehensive document from the Royal Society (see link at the end of this article), but here are some pointers.
There is a natural antipathy between the law, which attempts to discover and punish criminal responsibility, and neuroscience, which presents evidence suggesting that the accused is the creature of the brain which reduces and perhaps removes the freedom necessary for guilt. The case of the schoolteacher is clear but not typical. But the issues are of interest to us since they have a direct bearing on free will and so our understanding of virtue and sin. I will look at this latter question in another column but here I give a representative selection of some areas of legal interest.
What should be the minimum age for criminal responsibility? Neuroscience tells us that neural circuits controlling behaviour mature late, while the elements concerned with emotion and reward mature early. This suggests that we should raise the age from 10 to at least the mid teens, in line with several European countries.
We deplore violent anti-social behaviour without being aware that there may be a genetic fault which affects a vital neurotransmitter, or that this offender is unable to recognise the emotions of others, or that a psychopath may have damaging changes in his brain. And these are aggravated cases. Into human decision, as we know by introspection, enter a whole range of causes which may affect freedom.
But the lawyers are wary. They are used to considering the influences which act on a criminal and, while they accept the possibility of the distortions of the brain, as yet they have their doubts. For instance, they say that neuroscience looks at tendencies which are measurable in groups, but the law is concerned with considering the individual. They believe that university students, frequently used for group studies, may give atypical results. Nor are they blind to the fact that many published studies are corrupted by poor or dishonest methodologies.
They are wary of statistical interpretations. It will be a long time before they forget the expert who multiplied the chances of two cot deaths in a family, instead of adding them. They do not deny the possibility of neuroscience detecting relevant information but they do claim that it must prove its case.
There are other areas. An important one is the understanding of attention and memory. A witness, albeit reflecting accurately in his visual cortex, may only be attending consciously to certain features. Thus he may “misremember” an incident.
The accuracy of identification parades is questionable. Unconscious collusion between groups of witnesses can corrupt their memories. Suggestive police interrogation can infiltrate memories. False confessions are common. The decay of memory in short periods of time is not fully appreciated. Neuroscience can help here, although the reluctance of the courts to use its resources is regrettable. Juries are not invariably briefed on these inducements to error.
Given that old-fashioned lie detection methods are suspect, we might hope that brain scans would be more reliable. Unfortunately, this is an area where it is difficult to conduct studies which test realistic situations. People can learn effective countermeasures to give false readings, and the difficulty of detection, when a subject has come to believe the lie, remains. So far, the picture is not optimistic.
We may hope that developments in neuroscience in the future will enable the courts to detect the extent of responsibility more accurately. Indeed, some would wish for the concept of responsibility to be abandoned. In that case the survival of our legal system would depend on its utility through punishment to inhibit the temptation to anti-social behaviour. The very word “justice” would be otiose.
Certainly, a deeper understanding of motivation will be valuable in controlling crime, and we may learn much about matching punishment more closely to the individual criminal. This would include risk assessments when release or parole is being considered.
It is no secret that our system of legal sanctions does little to induce the criminal to conform – and may perhaps contribute to the problem. Any contribution here from neuroscience would be a boon.
So neuroscience can potentially join genetics and psychology as part of the evidence through which the law can better establish responsibility. We are still at an early stage but we must suppose that its contribution will grow as we learn more. Come and tell us what you think at Secondsightblog.net, where you will find a link to the Royal Society paper.
Link to Royal Society paper Neuroscience and the Law: http://royalsociety.org/uploadedFiles/Royal_Society_Content/policy/projects/brain-waves/Brain-Waves-4.pdf