review

Imagine Michael Howard standing up at the Conservative Party Conference, and announcing that he had a new get-tough policy with violent young offenders. From now on, he'd declare, with that singularly odious smirk of anticipation, they were going to be sentenced to play Pac-Man three times a week... whether they liked it or not. I don't suppose the hall would ring with the baying roar of satisfaction that follows Mr Howard's more conventional obeisances before the God of middle-class fear.

But, as the first part of A Mind to Crime (C4) cautiously suggested, such a regime might be considerably more productive than the institutional vindictiveness which characterises the government's current policy. Anne Moir and David Jessel's fascinating film on new research into the biological determinants of crime included the case of Danny, a 20-year-old with a long record of delinquency and crime. Danny has been identified as suffering from Attention Deficit Disorder, a condition in which the frontal cortex suffers from low levels of arousal. Because of this, it is far less efficient at controlling the limbic system, the brain's emotional centre. The result is a personality which is all accelerator and no brake. For some children, like Cody ("Cody's killed quite a few animals. When he was three he microwaved a cat"), the solution is chemical - paradoxically a brain stimulant, which improves his ability to concentrate and thus calms him down. For Danny the answer was biofeedback: by using his mind to control simple video- games he had improved his behaviour radically, re-entering school and passing his exams with distinction.

There were huge issues behind these simple findings, issues neatly encapsulated by a line of Jessel's elegant script - "Doesn't childhood deserve the presumption of innocence?" he asked, touching on the emotional furniture which clutters our understanding. In both programmes you saw snapshots and home movies of children who grew into killers - quietly posing the question of just when society's sympathies evaporate. As a child, Danny Wortham, damaged by his mother's drinking at birth and abandoned by her after it, is an object of uncomplicated pity; at 17, dealing crack cocaine and convicted of a senseless murder, he is an object of loathing and disgust. Where does the fault-line lie, when a victim becomes a victimiser?

There were fascinating conjectures in the second programme too - in particular, the finding that low levels of serotonin show a correlation with violent crime. This isn't, as some right-wing commentators suppose, an escape from arguments about social deprivation and inequity. Low self-esteem and low social ranking have the effect of depressing serotonin levels (it may be an unhappy evolutionary legacy - low ranking generates the sort of aggression which might push you back up the ladder). Alcohol further depresses serotonin, with predictable results. Sergeant James Moss, a Washington policeman and, on the face of it, no bleeding-heart liberal, was uncompromising: "If alcohol all of a sudden disappeared off the earth, almost 70 per cent of my job would go away."

The best thing about A Mind to Crime was that it enlightened without simplifying. If there are mechanistic explanations for human evil, does that mean that society can enforce mechanistic solutions? The neuro-scientist Adrian Raine suggested that better care and education for pregnant women from deprived backgrounds might reduce the crime rate by 18 per cent, a figure that seemed roughly as verifiable as Sergeant Moss's off-the- cuff calculation about drink.

It was clear, though, that this new knowledge could push us in many different directions. It is the sort of topic that might usefully be discussed at the Conservative Party Law and Order debate - but for the fact that, in that organism, the frontal cortex shows barely any signs of life at all.