Silver Screen Scientifics

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End-of-Life Does Not Imitate Art

Ioana Manea
Contributor

Law and Order, CSI, NCIS and Bones welcome viewers into forensic laboratories that resemble the actual working place of scientists such as those depicted on TV shows. Nevertheless, when the cinema set is transported from the small screen to real life, the investigation isn’t resolved within 45 minutes, the technological apparatus isn’t top-notch and science doesn’t provide all the answers. In other words, when the light gets brighter, everything else appears dimmer.

First and foremost, examinations requiring forensic scientists comprise of 60% natural-cause cases and only 2% homicides. Real life, as expected, is less exhilarating than a weekly show would lead us to believe.

Moreover, like a judge banging the gavel in court, DNA evidence repeatedly has the last word in TV shows. Indeed, hard proof doesn’t lie. But what do real life scientists do when the evidence at hand mumbles nonsense or simply doesn’t utter a word?

Well, as Tina Delgado, forensic DNA examiner in the FBI’s DNA Analysis Unit, says, “just because you can run an analysis doesn’t mean you’ll get results. […] Sunlight, heat, humidity, and age can all damage DNA. We have successfully analyzed material that had been in police evidence lockers at room temperature for decades, but DNA can go bad if left out in the sun for even a few days.”

More precisely, by having oily skin, washing your hands more or less often or by wearing lipstick, different people will be prone to leaving varying amounts of DNA behind.

Then, the DNA is processed through a genetic analyzer, which will inspect 13 different locations on the DNA. Those locations are not known to be linked to any typical physical trait but tend to offer a wide variations between individuals. Damaged samples will not contain all 13 sections, but will still allow investigators to rule out suspects.

As for fingerprints, “[t]he big difference is that on TV they usually find a single match, which pops up with a picture of the individual,” Michael Wieners, Chief of the FBI Laboratory’s Latent Print Support Unit declares. In real life, computers provide a list through which a person has to go through and compare each one of the prints on the screen to the sample one. That is because of the elasticity of skin which makes it inaccurate to overlay two images. However, before doing so, images are edited to remove any digital noise such as dirt. Nevertheless, only 26% of the cases received by a lab include accountable fingerprints.

Despite all this, most of us, when the credits roll, have the indubitable impression that forensic evidence and investigation techniques can solve any crime. Jurors are by no means different and hold the same unrealistic expectations, which has become such a prominent problem that it now has its own name: the CSI effect.

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