Critics Challenge Familial DNA Testing DNA results from a crime scene often don't lead to an exact match. Some investigators use DNA to find near-matches that could lead to a suspect. Critics say this practice, called familial DNA testing, invades the privacy of innocent people.
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Critics Challenge Familial DNA Testing

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Critics Challenge Familial DNA Testing


Critics Challenge Familial DNA Testing

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So in most of those 25 cases in Massachusetts, Luke, the administrator - Mr. Pino - is accused of failing to send on matches to law enforcement. But there are four cases where, actually, he sent in paperwork claiming matches when there were not exact matches.


Right. In those instances, the DNA evidence actually matched a family member of someone in the computer database. Now the Massachusetts state police say they don't officially condone using these familial links, as they're called, to investigate crimes.

And NPR's Tovia Smith has more on this controversial technique.

TOVIA SMITH: Of all the cold cases they couldn't solve, police in South Carolina were especially rattled by the brutal 1989 rape and murder of Joyce Robinson in Sumter. The 29-year-old victim was engaged to a state trooper, and many officers were there when Robinson was buried in her wedding dress. For 15 years, investigators followed up even the sketchiest of leads and kept running DNA tests on semen from the crime scene, but they kept coming up empty.

Chief PATTY PATTERSON (Chief of Police, Sumter Police Department): It was very frustrating when you know that you have a community out there saying, are we ever going to have any answers.

SMITH: Sumter police chief Patty Patterson says two years ago, she ordered yet another DNA test that finally hit. It wasn't an exact match, so police knew they didn't have their killer, but it was close enough so they knew the near match was probably the killer's brother or son. It was a huge break.

Chief PATTERSON: I was just elated that it was no longer out of our reach, and that finally, we are going to be able to say, yes, the day would come that we would get him.

SMITH: Using more old-fashioned police work, investigators quickly zeroed in on one brother. They ran his fingerprints and got a match to the crime scene. Police arrested him and got his DNA, and that turned out to be a perfect match, too. Three months ago, the man pleaded guilty and was sentenced to 30 years in prison.

Chief PATTERSON: The perpetrator was behind bars, and prayers had been answered.

SMITH: Around the nation, prosecutors are just beginning to discover how powerful so-called partial or familial DNA matches can be, especially compared to a police sketch, for example, or an anonymous tip.

Mr. MITCH MORRISSEY (Denver District Attorney): It's more than just your normal lead. It's a scientifically based lead that could solve a lot of cases.

SMITH: Mitch Morrissey is a district attorney in Denver who has three cases that have partially matched convicts in other states. The FBI used to forbid sharing that kind of near hit across state lines, but last summer, Morrissey got the federal government to temporarily change its policy and let states decide for themselves. Most have not yet done so, leaving Morrissey still frustrated.

Mr. MORRISSEY: We're running the risk of another victim, and if we had the opportunity to use this technology to try to capture that person and we didn't do it, then I'd say shame on you for not helping us here.

SMITH: But many say helping in that way would be hurting innocent people. Right now, DNA databases are primarily made up of convicted criminals. Some states also include people who've been arrested. When you start considering partial matches, you may lead police to the bad guy, but you also give them a window into the DNA of millions more people who are not criminals themselves but may just happen to be related to one.

Professor HANK GREELY (Professor of Law and Genetics, Stanford University): The idea that the sins of the fathers would be visited on the children, is a troubling one in our society.

SMITH: Hank Greely, professor of law and genetics at Stanford University, says what's most troubling are the larger racial implications. Since databanks are disproportionately made up of minorities, Greely says, the family members who get investigated will also be disproportionately minorities.

Prof. GREELY: It's one thing to say that it's okay to have felons have their DNA in the database, even those are disproportionately African-Americans, because they brought it on themselves by committing the crime, but now you're making suspects out of all of their relatives, and I think you could argue that that's unfair.

SMITH: Critics also worry where police will draw the line. Will a partial match be considered probable cause? Would family members have to give a DNA sample based on a partial hit?

Ms. TANIA SIMONCELLI (American Civil Liberties Union): We don't have any rules. You know, none of this has been worked out in any way.

SMITH: Tania Simoncelli with the ACLU says just because technology allows us to do family matching doesn't mean we should.

Ms. SIMONCELLI: I mean, we could put, you know, cameras in everybody's living rooms and say too bad, you know, and you could catch more criminals that way, but that's a bad way of making policy.

SMITH: Prosecutors say following up on partial DNA hits doesn't have to mean banging down doors. Police do a lot of investigating quietly, behind the scenes, but that's little comfort to Lauren Stephens(ph), a public defender who represented the South Carolina killer.

Ms. LAUREN STEPHENS (Public Defender, South Carolina): What exactly are they going to look at? And just because you don't know they're doing it, does that make it right? That's kind of Big Brother. That to me might even be scarier.

SMITH: But prosecutors say that kind of police work already happens all the time, and Denver DA Mitch Morrissey says police always have and always will questions people who turn out to be innocent. He likens a partial DNA hit to having an eyewitness who caught only half the license plate on a getaway car.

Mr. MORRISSEY: I think people would be outraged if the police just said oh, it's only a partial plate, so we're not going to follow this up. The nature of police work is you have to talk to a lot of people.

SMITH: And, Morrissey adds, the good news about partial matches is that if DNA leads police to someone who's innocent, that same DNA should also be able to clear that person just as fast. Tovia Smith, NPR News.

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