The Forensics Behind The N.Y. Bomb Attempt
ROBERT SIEGEL, host:
To find out more about the forensics behind this case, we turn now to Lawrence Kobilinsky. He's a professor of forensic science at the John Jay College of Criminal Justice at City University in New York.
Welcome to the program, Professor Kobilinsky.
Professor LAWRENCE KOBILINSKY (Forensic Science, John Jay College of Criminal Justice): It's a pleasure to join you.
SIEGEL: Firstly, in a place as busy as Times Square, how can investigators retrieve evidence without it being contaminated in some way?
Prof. KOBILINSKY: Well, you know, it certainly poses a problem when there are more people at the scene, but the first thing that is done is people are removed from the area and only authorized personnel should be there. And of the authorized people, everybody who enters the scene is documented. We want to take all steps to avoid any kind of contamination or tampering or moving evidence from one place to another. Everything should be very carefully documented.
SIEGEL: If a man drives an SUV for a day, let's say, is it likely or unlikely that he would leave a bead of sweat, a bit of hair, something that would give people DNA evidence to work on?
Prof. KOBILINSKY: I would say it's quite likely. However, everything depends on how much DNA is left behind. If it's a hair, and people lose hair, scalp hair, very commonly, that's a very important piece of information because the root can provide identifying information, and the shaft can provide information as well.
But I think in a vehicle like this one, we can be assured that some form of DNA was left behind. The question is, how much?
Typically, the crime scene unit will swab the steering wheel and the driver-side handle. It's necessary to pull on that handle to exit the vehicle. So we know that that was touched. And assuming the person was not wearing gloves or did not take steps to remove fingerprints and other types of evidence, I would expect to find DNA on those objects.
SIEGEL: Is it your experience that the forensics actually can lead to the suspect, or does the forensic evidence, typically, confirm that somebody, who in fact his brother-in-law, actually could no longer abide the knowledge that this guy planted a bomb someplace has turned him in?
Prof. KOBILINSKY: Sure.
SIEGEL: That is, does the forensics simply corroborate other evidence that meets the case?
Prof. KOBILINSKY: Well, yeah, there are only two kinds of evidence that can easily identify a particular suspect where you have nobody, and that is fingerprints and DNA. Now, we've heard that fingerprints are not going to be significant in this case, at least what the public is aware of.
On the other hand, DNA may be very significant. And, you know, in New York City, we do low-copy number DNA. This is - or high sensitivity testing DNA. So even if the perpetrator left 15 cells or even less, we enter that high sensitivity testing and we can develop a genetic profile. And if that person is on the national database or a local database or a state database, the police will be able to come up with a name.
SIEGEL: But isn't to that if, that is, if you found DNA and if that DNA happened to be in one of those registers, in one of those databases, isn't that a pretty big if?
I mean there hasn't been a great wave of car bombings in the United States, so it's not as though we could assume that somebody would already have been implicated in such an offense. What if this person is just for some cause fanatical and violent and not a criminal by nature?
Prof. KOBILINSKY: It certainly - that possibility exists. On the other hand, if a month from now, if we don't have anybody, no leads, no suspects, and a month from now, this fellow decides to jump a turnstile and he is required to give up a cheek swab of DNA, they'll have him then. So if it turns out he's not on the database, there is a good possibility in the future he will be caught based upon DNA.
SIEGEL: Dr. Kobilinsky, thank you very much for talking with us.
Prof. KOBILINSKY: My pleasure.
SIEGEL: Lawrence Kobilinsky, professor of forensic science at the John Jay College of Criminal Justice of the City University of New York.