The other day, friends of ours were raided by the Metropolitan police, who confiscated computers and digital storage devices on suspicion of paedophile activity. The couple had neglected to secure their modem with a password, but the police needed to make sure that the modem had indeed been “compromised”. After eight weeks, the computers came back with no evidence on them of child pornography. “It’s a horrible thing for you and your family to have gone through,” said the detective constable apologising for the unjust suspicion. A perfect stranger had apparently parked his car outside the family house and, using a smartphone, hacked into their Wi-Fi network.
Increasingly, cyberspace is where we are judged by others and, on occasion, even destroyed. Yet for all the advances in digital science, folk prejudices and pathologies remain. Evidently we still make judgments from facial stereotypes, as the facially deformed are persistently regarded as criminal or stupid. Forensic science as we know it evolved partly out of the crackpot ideas of the 19th-century Italian criminologist Cesare Lombroso, who believed that “born criminals” could be known by their anatomy. Social deviancy was written in a man’s jug ears, for example, or rodent-like incisors.
Lombroso’s systematic mug shots and fingerprints of presumed delinquents anticipated police identikit and photofit taxonomies, which crudely divide the human face into constituent parts (aquiline nose, pug nose, flat nose). According to Val McDermid, Lombroso’s anatomical stigmata influenced the outcome of countless 19th-century trials: how many were condemned unjustly for their low foreheads or other tell-tale atavisms?
While we no longer apply the notion of delinquent physiognomy to the study of crime, judges are known even today to give “good-looking” people more lenient sentences. Handle-shaped ears or devilish eyebrows can be a drawback in court. “Lombroso is an ass,” scoffs a character in Joseph Conrad’s The Secret Agent; McDermid, in her fascinating history of forensic science and its applications, agrees: “Lombroso went about it completely the wrong way.”
Yet the misguidedness of Lombroso’s theory does not diminish the value of his scientific method, which was exacting and recognised the sensory limits of knowledge (never believe anything until it is proved true). In order to solve crimes, some investigators today pay careful attention to human physiology, says McDermid.
In a gruesome chapter, “Entomology”, McDermid considers the relationship between insects and the deceased. A murder victim lying unclaimed and unmourned outdoors may crawl with maggots and glucose-hungry flies that feast on clots and wounds. In time the corpse may become silvered over entirely with insect saliva. Forensic entomologists must hurry to reach the body before it decomposes out of reach into the food chain. Importantly, maggots can indicate when flies laid their eggs on the corpse and therefore the point at which the victim was “definitely dead”, says McDermid.
Sherlock Holmes, the greatest scientist-sleuth, was able to distinguish at a glance the ash of any known cigar brand. His powers of deduction so impressed the Frenchman Edmond Locard that, in 1910, he decided to open the world’s first crime laboratory. “Every contact leaves a trace”: Locard’s observation hints at the rigours involved in the application of science to crime-solving. Biohazards such as third-party blood, vomit, sputum or faeces can fatally contaminate a crime scene and impede the pursuit of what Holmes called the “scarlet thread of murder”. The British legal system aims to put science squarely in the service of justice, apparently.
McDermid, 59, is the author of 28 crime novels; for this nonfiction work she has interviewed crime scene investigators (CSIs), ranging from blood spatter specialists to DNA swabbers, craniofacial reconstruction experts and footprint and toxicology analysts. They all, in their different ways, ensure that evidence is transferred safely from the crime scene to the courtroom. In charting the “astonishing leaps” that forensic science has made over the past two centuries, McDermid provides a grimly absorbing account of crime and its detection. At the Museum of Criminal Anthropology in Turin, meanwhile, Professor Lombroso’s head is preserved in formaldehyde; students say that its cranial bumps display a criminal tendency.
Forensics: The Anatomy of Crime is published by Profile (£18.99). Click here to buy it for £14.99
