Crime Labs Struggle with Flood of DNA Samples Crime labs are expanding DNA databases to include misdemeanants and arrestees as well as convicts. The effort may lead to more DNA matches from crime scenes. But now, a big backlog of evidence remains untested — while offenders may be committing more crimes.
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Crime Labs Struggle with Flood of DNA Samples

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Crime Labs Struggle with Flood of DNA Samples

Crime Labs Struggle with Flood of DNA Samples

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The databanks where DNA information is stored have grown steadily over the last 20 years. At first only samples from convicted felons were kept. Now some states and cities are taking DNA samples from everyone who's arrested.

Earlier today on NPR's MORNING EDITION, NPR's Ari Shapiro started a series on the ethics of DNA. For our show he examines whether bigger DNA databanks are better.

ARI SHAPIRO: Harvard professor and DNA expert David Lazer says if you want to get someone from a DNA lab aggravated...

Professor DAVID LAZER (DNA Expert): Just tell them, well, I assume it's all like what we see on "CSI."

(Soundbite of TV series, "CSI Miami")

Ms. EVA LA RUE (Actress): (As Natalie Boa Vista) Vasco Torres was packing this particular heat.

Mr. ADAM RODRIGUEZ (Actor): (As Eric Delko) That's the guy who set fire to his motorcycle.

Ms. RUE: (As Natalie Boa Vista) Now it looks like he killed Brian Partney.

Dr. PAUL FERRARA (Department of Forensic Science, Virginia): No. No, no, no. No, no. On the contrary. That just doesn't work that way.

SHAPIRO: Dr. Paul Ferrara created the first DNA database in the country in 1989 as head of Virginia's Department of Forensic Science.

Dr. FERRARA: You know, you can run thousands of convicted felon samples for every couple cases of crime scene evidence you run.

SHAPIRO: See, there are two parts of forensic DNA testing. The first part is building the database with samples from known offenders. That's quick, easy and relatively cheap.

The hard part, Ferrara says, is analyzing crime scene DNA.

Dr. FERRARA: It's very labor-intensive; it's not at all amenable to automation. So the laboratories are trying to keep up. None of them can.

SHAPIRO: If it costs around $100 to test an individual, it could cost more than $1,000 to test a crime scene.

There are backlogs of crime scene evidence all across the country waiting to be tested, and those backlogs have serious consequences. Ferrara remembers one case in Virginia where the forensics lab had a DNA sample from a rape. It took the lab a couple of months to realize that the crime scene DNA matched someone whose profile was in the database.

Dr. FERRARA: In the meantime, this guy had raped and murdered a woman by the name of Gemma Saunders.

SHAPIRO: Those kinds of stories are not uncommon. The Los Angeles Times recently reported that the L.A. Police Department has nearly 7,000 untested DNA samples from sexual assault cases in cold storage. A state audit said the LAPD would need more than $9 million to clear the backlog.

Chris Asplen is the DNA technology consultant who used to direct the National Commission on the Future of DNA Evidence. He says the backlogs can be attributed in part to expanding DNA databases.

Mr. CHRIS ASPLEN (DNA Technology Consultant): If a state changes its law to include a greater number of offenders, what has happened is you create an immediate backlog. You know, if you extend to everyone convicted of minor, you know, misdemeanors, immediately that day you have a backlog of everybody convicted of minor, you know, misdemeanors.

SHAPIRO: With a major expansion, a forensics department with a limited budget suddenly has to balance an existing backlog of crime scene samples with tens of thousands of known offenders who have to be added to the database right away.

Civil libertarians also have concerns about expanding databases. Law-enforcement groups like to say that giving police a DNA sample is no different from giving police your fingerprint.

Tania Simoncelli of the ACLU disagrees.

Ms. TANIA SIMONCELLI (American Civil Liberties Union): Whereas a fingerprint is basically just a two-dimensional representation of the tip of your finger, your DNA contains a great deal of information. It could be about susceptibility to disease as well as information about your family history. This is private, personal information about you that goes far beyond just identification.

SHAPIRO: Forensics labs could take one step that would make civil libertarians very happy. Right now labs hold actual biological samples from known offenders. Privacy advocates want the labs to throw out the full DNA sample and hang onto just the 13 loci, the points that scientists use to match a known sample to a crime scene; that way scientists couldn't search for illnesses or other private information.

Mr. TONY RACKAUCKAS: (District Attorney): Yeah, actually, it is something that's been considered, and we've decided not to do that.

SHAPIRO: Tony Rackauckas is the district attorney for Orange County, California.

Mr. RACKAUCKAS: You know, there's a possibility that it might have to be tested again.

SHAPIRO: In Orange County, a recent law mandates that anyone who pleads guilty to a misdemeanor must submit a DNA sample. Rackauckas says he hasn't had any complaints so far.

Mr. RACKAUCKAS: People who commit crimes commit a lot of different kinds of crimes. And I think that just the more offenders we have in the database, the more likely it is that we're going to be able to catch people who commit more serious crimes.

SHAPIRO: In Virginia, studies have shown that matches with crime scene samples increased as the database grew over the last 20 years. But there is a point of diminishing returns; after all, only a small percentage of the population commits the majority of crimes, so you won't get many matches beyond them. States and cities have to figure out where the line is and allocate scarce resources accordingly.

Ari Shapiro, NPR News.

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