Television crime shows aren’t reality TV

Photo courtesy of CBS ©2012 CBS Broadcasting, Inc. All rights reserved.

Television dramas like CBS’ CSI: Crime Scene Investigation have brought attention to DNA analysis, but Tim Kupferschmid, executive director of Sorenson Forensics, frequently finds himself correcting misinformation about his work. He calls the disconnect the “CSI effect.” Kupferschmid’s list of the top TV myths:

Myth: Crime scene investigators (CSIs) and forensic lab scientists are one and the same.         

Fact: They belong to separate professions and rarely, if ever, cross paths. CSIs are usually police officers without a science degree. Forensic scientists have advanced training in biology, chemistry and forensic science. CSIs collects evidence at the scene, which forensic scientists analyze in the lab.

Myth: Forensic scientists visit crime scenes and join police raids.                      

Fact: They rarely leave the lab, ruling out emotionally charged subplots and exciting shoot outs.

Myth: DNA evidence is slathered on every object the suspect touches.
Fact: It takes sustained contact to transfer DNA, and not all surfaces capture it.

Myth: Evidence of a person’s DNA at the scene of the crime means the suspect is guilty.

Fact: DNA from many people is usually found at a crime scene. “It takes old-fashioned gumshoe detective work to determine guilt,” Kupferschmid says. 

Myth: DNA evidence found at a crime scene is analyzed immediately.

Fact: DNA labs nationwide have a backlog ranging from several weeks to years.

Myth: DNA results are instantly generated at the laboratory.                       

Fact: It takes about five days to produce a DNA profile. 

Myth: TV CSI labs crackle with case discussions, verbal sparring and sexual innuendos.

Fact: Real labs lean toward a monastic quiet, and the real lab’s coiffure and fashion sense is sorely lacking. “We are gowned up in lab coats and tiebacks, gloves and face shields,” says Kupferschmid. “Simply talking over the evidence can contaminate the DNA.”

Myth: Database searches produce complete information on a suspect, including a photo.          

Fact: The real lab’s computer spits out a simple number code that can be fed into the FBI’s CODIS database. Time on the database is rationed. A hit, if there is one, can take weeks.

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