STEPHEN MERCER (Attorney): DNA between persons who are related is vastly more similar than DNA between persons who are unrelated. So when the government has the DNA of one family member, in effect, they have the DNA of that person's siblings, children and parents.
SEVERSON: Here's how it works. DNA from a crime scene is run against the nearly six million samples on file. If there's a partial match, it likely means that a relative of someone in the database is guilty of a crime. This kind of testing could open up a whole new realm of possibilities for authorities. But critics warn that is could mark the beginning of dragnets, sweeping in people who are completely innocent and possibly violating their Fourth Amendment rights against unreasonable searches and seizures. Sonia Suter is a bioethics professor and she's concerned that people will see only the benefits of familial testing and not the threat to personal privacy.
Professor SONIA SUTER (George Washington University Law School): There's a lot of kinds of uses of this -- of these samples that sound great. They look good on programs like "CSI" but they might involve probing too deeply into very personal information. Could the police decide they want to do broad scale research on these samples, and start investigating the samples for links to certain kinds of illnesses, or certain kinds of propensities for behavior?
SEVERSON: Professor Suter says familial testing without safeguards may be only the beginning of a very slippery slope.
Prof. SUTER: I think people might start to feel differently about this if they imagined all of the information that could potentially be obtained. And it will only get easier to do as we identify more genes. It will only be cheaper as the technology advances.
SEVERSON: Constitutional law professor Jeffrey Rosen says the use of familial testing could signal a dramatic challenge to American civil liberties.
Professor JEFFREY ROSEN (George Washington University Law School): There's a very profound moral lesson. My mother taught it to me actually. She said, "You should be responsible not for what you think but what you do." And yet that idea is really being challenged by an idea of genetic surveillance that would hold people accountable not for wrong doing but for wrong being.
MITCH MORRISSEY (District Attorney, Denver): There is no privacy right that is being violated by doing familial searching.
SEVERSON: Mitch Morrissey, the District Attorney of Denver is a vocal advocate for familial searching. He says it's just another tool to track down leads, the way police use partial license plates and fingerprints.
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