Commander of the county crime lab
By Ellen F. Harris
Photograph by Scott Rovak
Lt. Kevin Lawson shakes his head in frustration and clicks off CSI: Crime Scene Investigation. “This show gives other police officers—and judges, prosecutors, defense attorneys, and jurors—unrealistic expectations about what can be done and how quickly,” he says. “CSI wraps up a case in 48 minutes, because it’s the only one going, so they dedicate their entire lab to it. Our reality is juggling lots of cases.”
Lawson commands the St. Louis County Police Department Crime Laboratory, in Clayton, where 18 scientists perform forensic tests using DNA and other biological materials, chemistry, firearms, tool marks and photography so police can figure out whodunit in 10,000 or so cases involving drugs, weapons and violent crimes every year. With yet another season of forensics procedurals under way on TV, Lawson helped us separate the fact from the fiction.
Are you as fascinated with forensics as the layperson? Well, yeah. It’s still amazing to me how trace evidence can conclusively ID an individual.
How do forensic TV shows affect what you do? A prosecutor watched a CSI episode in which scientists identified concrete dust from the victim’s fingernail, nailing the suspect. The next morning, he called us to see if we do that here. We’d never heard of such a test. Or take DNA: An officer brought in evidence he wanted tested, and when we told him it would be six to nine months because of the backlog, he asked, “Don’t you just feed it through the side of a machine?”
In what ways is CSI off? In real life, the tests are laborious and painstaking. Their scientists issue a one-page report. We print out 45 to 55 pages in detail about each step, and that is reviewed by a second qualified analyst—then we release the report. CSI would have you believe it’s a snap to compare and analyze firearms; the reality is, it takes up to a month to analyze a possible match.
So does CSI make you feel inferior? We are, in general, better than TV forensic scientists, because we don’t get the opportunity to select our cases or always have pristine evidence. We have to make do with what police can recover. And in court, we have to testify correctly the first time, unlike on CSI, where the director can say, “Cut. Take two.”
So are these TV shows ever accurate? Yes. We can connect multiple cases and crimes in different jurisdictions to the same offender before we even know his name. A burglar left blood at a Creve Coeur crime scene that we entered into CODIS [the nationwide Combined DNA Index System], and a hit connected him to a burglary a year earlier in St. Charles.
Why do you think the public is so fascinated with forensics? Because forensics can seemingly ID suspects out of nothing. The O.J. trial gave a boost to this, and nearly every so-called crime of the century has used forensics. Take the Lindbergh-baby kidnapping: Bruno Hauptmann was convicted in part through forensic botany. Scientists matched the grain of the ladder found at the Lindberghs’ house to lumber found in Hauptmann’s attic.
What is our biggest advance? The nature of DNA testing. We used to need a sample the size of a quarter, and now we only need evidence the size of a pinhead to make an identification. We’ve reopened old homicides in our Cold Cases Project with Joe Burgoon [the retired St. Louis Metropolitan Police homicide sergeant]. What we call our “Crick”—after Watson and Crick—the ABI 310 Genetic Analyzer, produces a DNA profile from blood or semen.
What are your coolest new toys? Besides the 310, I’d pick the FTIR, the Fourier-transform infrared spectroscopy, which analyzes unknown compounds. The FTIR can differentiate one drug compound from another, like crack from cocaine or Sudafed, which is used in methamphetamine production. You put a tiny speck of a crystal on its artificial diamond lens, and the FTIR shoots infrared beams through the crystal to create a color spectrum.
Any other pet toys? The National Integrated Ballistic Identification Network, combined with the Integrated Ballistic Identification System. IBIS is a visual library search. NIBIN/IBIS is a wonderful instrument that correlates and matches ballistic evidence, like a gunshell, across jurisdictional lines. Say we have a casing from a shooting in Overland that matches on NIBIN/IBIS with a casing found at a murder in Rolla. A scientist can compare the two casings side by side like fingerprints. NIBIN/IBIS got a lot of press when it was used in the Washington, D.C., sniper cases.
You were a crime-scene investigator for 15 years. What was the most important thing you learned? Not to muck up the crime scene. The more pristine the scene, the more we can recover viable and probative evidence. I like to quote Locard’s Theory of Exchange: Whenever two objects come into contact with each other, there is always an exchange of evidence. Think of a triangle between the suspect, the victim and the crime scene. The perpetrator’s shoes may pick up a fiber from the crime-scene rug; the rug may contain a drop of the victim’s blood. Even if the victim is moved, the evidence from the scene goes with him.
