'CSI' not reality
By Jenny Welp Journal staff writer | Posted: Tuesday, October 25, 2005
Woodbury County crime analyst deputy Scott Lanagan sets up an imager to check for fingerprints on a fuel can suspected of having been used in a clandestine methamphetamine lab. the $19,000 imager allows Lanagan to image prints that are difficult to detect using traditional methods. (Staff photo by Tim Hynds)
Lisa Serres watches "CSI" as much as she can.
She said the program airs so often, she could see 12 episodes every week. But as a history major and biology minor at Morningside College, the 19-year-old has other things to do.
So she limits herself to three hours of "CSI" each week.
"I love 'CSI,'" said the young lady from Harrison, Neb. "It's one of my favorite shows because they use science to fight crime."
Serres is not alone.
"CSI" is the most popular show on primetime network television, according to the latest weekly report from Nielsen Media Research.
While the TV show is obviously entertaining, local crime scene analysts say the program does not give an accurate picture of their work. And a local prosecutor said the fiction could impact reality through the criminal justice system.
Watching "CSI," one could develop the expectation that DNA, fingerprints and tire tracks are left at every crime scene, said Scott Lanagan, senior crime scene analyst with the Woodbury County Sheriff's Office.
In reality, he said that's simply not the case.
For example, only certain surfaces can hold a fingerprint. And if people slide their fingers across a surface -- rather than pressing their fingers straight down and then lifting them straight up -- they can smudge the identifying features of their fingerprints.
When the actors on "CSI" find a fingerprint, they scan it into their computer, and that fingerprint shows up on one side of a computer screen.
Then on the other side of the screen, TV viewers watch as the computer quickly scrolls through suspects to almost instantaneously find a match to the fingerprint.
In actuality, Lanagan said he has to scan a fingerprint into the computer, use a cursor to highlight unique features of the fingerprint and then run a computer search to find possible matches.
He said he'll get 18 possible matches. Then he has to physically check the computer responses to see if any result in a match. Usually if there is a match, the computer lists that fingerprint first, but Lanagan said he recently matched a fingerprint with the computer's third listed response.
"There's no way they can show you all the work, all the processing that's involved," Lanagan said.
But things are better than they used to be, said Zac Chwirka, crime scene analyst with the Sioux City Police Department. Chwirka said crime scene analysts used to file known fingerprints on cards according to a formula -- similar to the card catalogs once found in libraries. At least now they have a computer database.
Besides fingerprints, "CSI" episodes also use shoe tracks or tire tracks to help solve a case.
But in real life, it's tough to go beyond discovering the brand of shoe or tire to finding the unique characteristics that identify that shoe or tire specifically and the person who owns it, said Sheila Rogeness, crime scene analyst with the Sioux City Police Department.
Assistant Woodbury County Attorney Mark Campbell said he takes precautions to make sure jurors always know that the stories on "CSI" aren't real. Otherwise, he said the jury could come up with a not guilty verdict because compared to what they've seen on television, there is a lack of scientific evidence.
Campbell always asks potential jurors if they watch police shows like "Law & Order" and "CSI." He said usually half of them say yes, and then he makes sure they understand that real life is different from television -- that these shows are not documentaries.
For example, Campbell said it takes a biological sample like semen, saliva or blood to collect DNA evidence, and suspects do not leave biological samples at crime scenes very often.
However, Campbell said there are exceptions.
Campbell remembers a few years back when a criminal helped herself to a can of pop during a robbery, and then left the pop can at the crime scene. He said investigators were able to identify the defendant through DNA collected off the pop can.
"That was a 'CSI' moment, but they don't happen every day," Campbell said. "When it happens, it's so cool."
She said the program airs so often, she could see 12 episodes every week. But as a history major and biology minor at Morningside College, the 19-year-old has other things to do.
So she limits herself to three hours of "CSI" each week.
"I love 'CSI,'" said the young lady from Harrison, Neb. "It's one of my favorite shows because they use science to fight crime."
Serres is not alone.
"CSI" is the most popular show on primetime network television, according to the latest weekly report from Nielsen Media Research.
While the TV show is obviously entertaining, local crime scene analysts say the program does not give an accurate picture of their work. And a local prosecutor said the fiction could impact reality through the criminal justice system.
Watching "CSI," one could develop the expectation that DNA, fingerprints and tire tracks are left at every crime scene, said Scott Lanagan, senior crime scene analyst with the Woodbury County Sheriff's Office.
In reality, he said that's simply not the case.
For example, only certain surfaces can hold a fingerprint. And if people slide their fingers across a surface -- rather than pressing their fingers straight down and then lifting them straight up -- they can smudge the identifying features of their fingerprints.
When the actors on "CSI" find a fingerprint, they scan it into their computer, and that fingerprint shows up on one side of a computer screen.
Then on the other side of the screen, TV viewers watch as the computer quickly scrolls through suspects to almost instantaneously find a match to the fingerprint.
In actuality, Lanagan said he has to scan a fingerprint into the computer, use a cursor to highlight unique features of the fingerprint and then run a computer search to find possible matches.
He said he'll get 18 possible matches. Then he has to physically check the computer responses to see if any result in a match. Usually if there is a match, the computer lists that fingerprint first, but Lanagan said he recently matched a fingerprint with the computer's third listed response.
"There's no way they can show you all the work, all the processing that's involved," Lanagan said.
But things are better than they used to be, said Zac Chwirka, crime scene analyst with the Sioux City Police Department. Chwirka said crime scene analysts used to file known fingerprints on cards according to a formula -- similar to the card catalogs once found in libraries. At least now they have a computer database.
Besides fingerprints, "CSI" episodes also use shoe tracks or tire tracks to help solve a case.
But in real life, it's tough to go beyond discovering the brand of shoe or tire to finding the unique characteristics that identify that shoe or tire specifically and the person who owns it, said Sheila Rogeness, crime scene analyst with the Sioux City Police Department.
Assistant Woodbury County Attorney Mark Campbell said he takes precautions to make sure jurors always know that the stories on "CSI" aren't real. Otherwise, he said the jury could come up with a not guilty verdict because compared to what they've seen on television, there is a lack of scientific evidence.
Campbell always asks potential jurors if they watch police shows like "Law & Order" and "CSI." He said usually half of them say yes, and then he makes sure they understand that real life is different from television -- that these shows are not documentaries.
For example, Campbell said it takes a biological sample like semen, saliva or blood to collect DNA evidence, and suspects do not leave biological samples at crime scenes very often.
However, Campbell said there are exceptions.
Campbell remembers a few years back when a criminal helped herself to a can of pop during a robbery, and then left the pop can at the crime scene. He said investigators were able to identify the defendant through DNA collected off the pop can.
"That was a 'CSI' moment, but they don't happen every day," Campbell said. "When it happens, it's so cool."
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