The Mystery of Murder: a Horizon Guide, BBC4 - TV review: Never mind the serial killers, are scientists the real psychopaths?

The psychopath-like behaviour of research scientists in general made for an intriguing subtextual theme

In for the kill: Michael Mosley presented 'The Mystery of Murder: a Horizon Guide'

The latest Michael Mosley-fronted science programme, The Mystery of Murder: a Horizon Guide on BBC4, wasn't its own documentary, so much as collection of clips from others in the Horizon archives. Mosley wanted to know what makes people murder. Is any individual capable of this most heinous crime? Or are some people truly born to kill? Unusually for BBC4, these questions weren't simply left to percolate, but were instead given fairly definitive answers.

Over the course of 50 years, Horizon films made on this topic have observed certain differences in the brains of convicted murderers again and again. These include an excess of testosterone, a lack of serotonin or an undeveloped pre-frontal cortex, yet because of the complicated interaction of environment and biology, we are still a long way off an entirely eugenics-led criminal justice system. And thank God for that.

The importance of upbringing was most effectively illustrated, not by any of the grisly serial killer portraits, but in the story of Professor Jim Fallon. While researching the brain abnormalities of murderers he'd been alarmed to discover 16 killers in his own family tree. Fallon decided to undergo testing himself, and discovered he fit the profile. Fortunately, he'd largely been able to escape his biological destiny thanks to a loving childhood. Although not entirely. "I always knew there was something off," said Fallon's adult son.

This might have been an appropriate juncture to include that clip from 2011's The Brain: a Secret History in which it was revealed that Mosley himself scores highly for traits of psychopathy, but strangely this was omitted. Still, the psychopath-like behaviour of research scientists in general made for an intriguing subtextual theme. You can only watch so much black-and-white footage of baby monkeys being tortured with electrodes, before you begin to wonder whether a lack of empathy is endemic in the profession.