I have come to the conclusion that many of the scientists, lawyers and law enforcement officers at the annual meeting of the American Academy of the Forensic Sciences are severely damaged people, writes James Randerson. Years of contact with the most depraved, gruesome, sickening and evil of human acts have, I think, changed them in frightening ways.
Just to give you a flavour of what these people deal with on a daily basis, here's a quick skim through some of the abstract titles at the meeting:
* Consensual flogging is not physical abuse
* Extra-genital injuries in sexual assault
* Unusual suicide with a chainsaw: a case report
* The effects of household corrosive substances on human bone and teeth
* Suicidal hanging resulting in complete decapitation: a case report
* Strangulation in sexual assault
* Killer hairdryer
And the slightly more light-hearted:
* Beetle poop: interpret with caution in south-east Texas
That is some day at the office!
I want to say at this point that I have the greatest admiration for forensic scientists' courage, professionalism and skill. They have the power to alleviate great human suffering by giving grieving families emotional closure when they identify a body or by leading police to a kidnapper's hideout.
However, I often detect a certain machismo when it comes to describing the most sickening cases. There is always the point in the talk where the scientist brings out the slide of the victim as she was found - usually hideously assaulted - and then leaves a slight theatrical pause to take in the audience's shock. Then it is on with a matter-of-fact description of the scene, as if the scientist were describing a doll's house.
This one-upmanship is most obvious in the "bring your own slides" session for which speakers save their most shocking, sadistic and downright horrible slides. I must admit, though, I was curious to go along.
On Tuesday a talk by Dr Michael Welner, a forensic psychiatrist at New York University, confirmed that being exposed to violent crime does seem to change you. He runs a project called depravityscale.org, an online questionnaire that aims to find out what aspects of crime people find most depraved.
More on this work later, but one finding from the study should give lawyers and forensic scientists pause. One group stuck out from the rest as rating nasty aspects of crimes as being less depraved than everyone else - the criminal lawyers. Regular contact with darkest corners of the human soul does seem to change your perception of evil.
Science correspondent James Randerson is at the American Academy of Forensic Science conference in Seattle
