Advocates of rapidly growing databases of criminals’ DNA say they’re a potent crime-fighting tool with little downside for law-abiding citizens. Typical of this school is Howard Safir, New York City’s Police Commissioner, who told the New York Times last summer: “We should be collecting [DNA] from everybody. The only ones who have anything to worry about from DNA are criminals.”
Well, not quite. British officials admitted in January that robbery scene DNA matched to England’s databank of 660,000 genetic profiles of convicts and arrestees had led to the arrest of an innocent man. The odds against two people having DNA fingerprints similar enough to cause such a mismatch are huge-about 37 million to one. Nevertheless, further testing and a string of alibis later proved that police had detained the wrong person.
The false arrest, say privacy and prisoner’s rights advocates, highlights ongoing problems with the proliferating criminal DNA databases. The FBI-maintained National DNA Index System (NDIS), begun in 1998, now contains 215,000 DNA fingerprints. Each state already requires prisoners convicted of offenses ranging from murder to intimidating a witness to submit DNA specimens. By the time all 50 states join the national system in 2002, the FBI predicts NDIS will contain more than 600,000 genetic profiles and will be growing at the pace of 100,000 new profiles per year.
The enlargement of NDIS has attracted criticism from civil rights groups, who question the constitutionality of taking DNA from a convict without a search warrant. And privacy advocates fear that geneticists might use the cache of convicts’ blood to search for a genetic basis for criminal behavior.
Few existing state or federal laws set clear rules for the fate of the DNA samples, which many states save indefinitely. “It’s one of the biggest problems with the system now,” says Chris Asplen, director of National Institute of Justice’s Commission for the Future of DNA Evidence. “Vague regulations leave the system open to abuse.”
Despite these concerns, lawsuits filed to stop DNA databases have not fared well. In a case brought by the Massachusett’s public defender’s office and the local chapter of the American Civil Liberties Union, the state supreme court ruled last November that a warrantless examination of a convict’s genome does not violate the Fourth Amendment’s protection against unlawful search and seizure because the resulting DNA fingerprint will be used for “identification” only, a purpose permissible under the constitution.
Still, as NDIS grows, the chance of DNA “misidentifications” will grow, too. “There’s a greater chance that you’ll find a close match as the databases get bigger,” says Paul Bresson, an FBI spokesman.
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