Adrian Raine, Professor of Criminology & Psychiatry at the University of Pennsylvania, was the first psychologist to study the brains of murderers. After doing PET scans on the brains of 41 murderers and 41 control test subjects at a lab at UC Irvine, Raine found significant results. Compared to the 41 control subjects, brain functioning in the very front of the prefrontal cortex in the 41 murders was very poor. The prefrontal cortex is the part of the brain responsible for our highest order tasks - decision making, impulse control, and emotional regulation. As you would imagine, if your brain has a harder time making decisions, controlling impulses and regulating emotions, you might be more likely to have angry turn to rage, and rage turns into homicide.
Criminologists and geneticists around the country are looking to the genetics of criminology. While they know there is no “crime gene,” markers for aggression and antisocial behavior could play a role in a criminal's activity. For example, Terrie E. Moffitt, a behavioral scientist at Duke University discovered a gene linked to violence that alters the production and regulation of serotonin in the brain. They also found that the gene is most often triggered to “turn on” by stress.
Both Raine and Moffit’s findings about criminal nature are incomplete without the measure of nurture. As the New York Times reports, “genes are ruled by the environment, which can either mute or aggravate violent impulses. Many people with the same genetic tendency for aggressiveness will never throw a punch, while others without it could be career criminals.”
Nurture could start as early as in the womb. Mothers that smoke or drink while pregnant double or triple the odds of a baby becoming a violent offender later. In childhood, poor nutrition nearly triples the rate of antisocial personality disorder in adults.
This raises the question that Adrian Raine puts well in his interview on Fresh Air, "if bad brains do cause bad behavior, if brain dysfunction raises the odds that somebody will become a criminal offender — a violent offender — and if the causes of the brain dysfunction come relatively early in life ... should we fully hold that adult individual responsible?"
What does the biology of criminology mean for the law?
There are several theories about what the biology of criminology means for the practice of law. The first is genetic consideration. Genetic consideration asserts that not all criminals are created equal biologically, so not all criminal offenders should receive the same punishment for the same crime. People who commit crimes that are proven to be under the influence of brain dysfunction and genetic make-up out of their control should be sentenced using less harsh tactics.
The opposite is deterrence theory. Deterrence theory disregards genetic consideration altogether, by arguing that the fear of punishment should deter people from committing crimes, regardless of their biology. Criminologist Amanda R. Evansburg argues “while evidence of a genetic predisposition to violent behavior may potentially be significant, it would be imprudent, as well as politically infeasible, to allow genetic determinism to substitute for the assumptions of free will in the criminal law.”
What do you think? What should be the future of genetics and the law?