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From DNA of Family, a Tool to Make Arrests

To Phyllis Hedge, daughter-in-law of a BTK victim, it is justified by the need to stop violent criminals. Her mother-in-law, Marine Hedge, was stalked and strangled by BTK in 1985. Twenty years later, Hedge said, she and her husband, Tommy, were stunned and elated to see on television a picture of her mother-in-law with news of BTK's arrest. In 2005, Rader was sentenced to 10 consecutive life terms.

"Whatever it takes to catch these people who do these atrocities, who have no respect for human life, whatever it takes to get them, is totally appropriate. . . . I'm grateful to [Kerri Rader]," she said.

Landwehr said he spoke with Kerri after her father had been arrested and that "she had no problem" with the use of her Pap smear. "What we had to do, we had to do," he said. "She understands that." Through her husband, Kerri Rader declined to comment.

Matching the Markers

To match DNA from tissue samples -- skin left under fingernails, semen on a car seat, saliva traces on a water glass -- forensic scientists examine the information contained at 13 locations on the human genome. Two genetic markers -- one from each parent -- are scrutinized at each of those locations, creating a profile of an individual that can be compared against a database of criminals. A match on all 26 markers -- called alleles -- is a perfect hit, indicating the samples come from the same person. A match on at least 16 alleles, especially if they involve a rare one, could indicate that a close relative left a sample, experts said.

"It's an extremely powerful tool," said Mitch Morrissey, Denver District Attorney. Not using it would be a wasted opportunity, he said. "It's like you build a Porsche and you drive it like a Pinto."

But one area that has civil libertarians greatly concerned is the potential to apply the technique to local databases unregulated by the stringent rules that apply to the national database and its state counterparts. Last September, Denver conducted the first test in the United States of familial searching software on a DNA database, using the county's databank of 1,700 profiles. Along with profiles from suspects, it also included lab employees and people who allowed their DNA to be taken to eliminate them as suspects. The people who were not suspects signed waivers, Morrissey said, allowing their DNA profiles to be used for research.

The test yielded three partial matches that, with additional testing and analysis, reflected a 90 percent likelihood relatives were involved -- one between a convicted felon and his brother, a rapist, and another between a prison inmate and his son, a burglar.

The third match linked a rape case suspect with the DNA profile of a lab employee. The suspect, it turned out, was the employee's brother. When investigators followed up, they found the case had been closed. "So there was no reason" to inform the employee that his brother had been identified through his DNA, Morrissey said.

"That's precisely the concern," said Stephen Mercer, a Rockville attorney specializing in DNA issues. "The trolling of rogue databases for information about family members is doubly invasive. It makes the persons in the databases -- many who are innocent -- genetic informants about their family members. And it extends that suspicion to their family members."

Morrissey said: "There is no inclusion of DNA that we don't have legally."

Other states and localities maintain "offline" DNA databanks of samples taken from victims or suspects never charged with a crime. Such databases, which also exist in New York, are a violation of the constitutional ban on unreasonable search and seizure, said Barry Scheck, a commissioner on New York state's Forensic Science Review Board. "If I get a sample from you and I don't tell you I want to put it in the database, that violates the scope of the Fourth Amendment," he said.

Prince George's County, for example, maintains a database with DNA profiles of both victims and suspects. Such local databases "have literally no oversight and regulation and yet are pushing the boundaries farther than anyone could imagine," said Patrick Kent, chief of the Maryland public defender's forensic division. "I do not think that victims of crime would be pleased to know that in addition to having been a victim, their DNA profile has been surreptitiously placed into a DNA database."


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