Television scrambles the evidence

摘要

Forensic science's spell in the limelight has given it huge kudos. Glitzy TV shows like CSI: Crime Scene Investigation have sent students flocking to forensics courses. But while this interest is sexing up the image of scientists, is it also stopping police catching criminals and securing convictions? "Jurors who watch CSI believe that those scenarios, where forensic scientists are always right, are what really happens," says Peter Bull, a forensic sedimentologist at the University of Oxford. It means that in court, juries are not impressed with evidence presented in cautious scientific terms. Detective sergeant Paul Dostie, of Mammoth Lakes Police Department, California, found the same thing when he conducted a straw poll of forensic investigators and prosecutors. "They all agree that jurors expect more because of CSI shows," he says. And the "CSI effect" goes beyond juries, says Jim Fraser, director of the Centre for Forensic Science at the University of Strathclyde, UK. "Oversimplification of interpretations on CSI has led to false expectations, especially about the speed of delivery of forensic evidence," he says.